   ### Kaushik B Male, 56 Years

Associated for 4 Years 10 Months
Preparing students for Success in Life
MBA & BBA Tutor

#### Activity Score - 3350

• I teach at My Home
• Online
Area: Wasseypur
Qualification :
• M.Pharma (Jadavpur University, Kolkata - 1986)
• MBA/PGDM (Asian Institute of Management - 2004)
• Total Experience:
7 Years
• Hourly Fees:
INR 1000
Tutoring Experience :

Teaching is my passion and I have been teaching since I was in engineering college. I believe in "Learning" and not in "Mugging" After taking a sabbatical from my professional career I have been associated with an institute for past 3 years where I teach maths & sciences.

Tutoring Option :
Online Tuition Only
Tutoring Approach :

My approach is to first identify the need of the student because each student has different learning ability and learning style. • Develop a plan along with the students so that he/she enjoys the learning. • Break the topics into chunks which will follow a logical order with a clear learning goal. • Each learning sessions will be interactive where I will use audio-visuals, charts, videos, and illustrations. • Key concepts will be repeated several times so that it builds the foundation of the student • Subject-wise, chapter/topic wise discussion, and solution in the session • Regular test analysis of student performance and regular feedback to parents on the progress of the students My teaching style will Stop Mugging and help the student to start Learning

Teaches:
 Class 9 - 10 Mathematics Physics Chemistry All Boards INR 500 / Hour Test Preparation CMAT INR 1000 / Hour MBA & BBA Management Subjects INR 1000 / Hour
• ## Question: A company declared 15% dividend on shares, whose nominal value is Rs. 150. A per...

Posted in: Mathematics | Date: 20/08/2017

Nominal Value (par value) of the share is Rs. 150. Nominal Value of 1000 share owned by the person= 150 X 1000 = Rs. 150,000.00 Comapny declared 15% dividend. Dividend amount = (15/100)X150X1000=Rs 22,500.00 (Dividend is calculated on nominal value and that is the sum received by the investor) Let the cost of each share purchased be "s".( the purchase price of a share is normally higher/different than nominal value) The person earned 12% profit on his investment amount= 1000s ( s X 1000 share) Then (12/100)X 1000s= 22,500.00 (since profit, = sum received from an investment) Therefore s= (22,500x100)/(12X1000)= Rs 187.50. Ans: Cost of each share bought was Rs 187.50

• ## Question: If Raju invests Rs. 24,000, and earns dividend at 10% for the face value of Rs. ...

Posted in: Mathematics | Date: 20/08/2017

Raju invested Rs, 24,000.00 for buying share quoted at Rs 48.00 Therefore Raju purchased (24,000/48) =500 shares. The face value of each share is Rs. 60 10% dividend on each share =(10/100)X60=Rs 6 Therefore total dividend earned on 500 shares =Rs 500X6=Rs. 3,000.00 Ans: Raju's income is Rs 3,000.00

• ## Question: In Ram's saving bank account, the amount qualified for paying interest of 4% for...

Posted in: Mathematics | Date: 20/08/2017

Amount qualified for paying interest @4% in June is Rs 4,500.00 Simple Interest = (P x R x T)/100 where Principal = P, Rate = R% per annum (p.a.) and Time = T years. (i) I = 4500X4X1/(100X12) since T =1 month=1/12 year Interest for June = Rs 15.00 (ii) Interest for July = 8500X4X1/(100X12)= Rs 28.33

• ## Question: Help me to calculate his monthly instalment if Rohan gets Rs. 7,725.00 at the en...

Posted in: Mathematics | Date: 20/08/2017

Maturity value of a recurring deposit is calculated by the following formula M = ( R x [(1+r)n - 1 ] ) / (1-(1+r)-1/3) Where, M = Maturity value R = Monthly Installment r = Rate of Interest (i) / 400 (Annual interest rate converted into quarterly rate) n = Number of Quarters (Assuming the compounding is done quarterly) 7725= (R* ((1+7/400)^8 - 1 ) ) / (1-(1+7/400)-1/3) R=299.18 (nearest approximation) Ans: Monthly instalment will be Rs 299.18

• ## Question: 'X' mL of 0.05 M solution of a double salt Na2CO3·NaHCO3·2H2O is titrated agai...

Posted in: Chemistry | Date: 21/08/2017

Titration of Na2CO3 using phenolphthalein as indicator involves the reaction: Na2CO3 + HCl = NaHCO3 + NaCl so 1 Mole Na2CO3 consumes 1 Mole HCl or "x" ml 0.05 M Na2CO3 soln consumes "x" ml 0.05 M HCl soln. so A = x. Titration of Na2CO3 using methyl orange as indicator involves the reactions: Na2CO3 + 2HCl = H2CO3 + 2NaCl and also NaHCO3 + HCl = H2CO3 + NaCl so 1 Mole Na2CO3 consumes 2 Moles of HCl and 1 Mole NaHCO3 consumes 1 Mole of HCl so "x" ml 0.05 M Na2CO3 soln consumes "2x" ml 0.05 M HCl soln. and "x" ml 0.05M NaHCO3 soln consumes "x" ml 0.05 M HCl soln. (as the compound contains both Na2CO3 and NaHCO3 in equimolar proportion) hence B= 2x+x=3x. TherforeB/A=3x/x=3:1

• ## Question: The ratio of monthly incomes of two employees is 3 : 5 and their monthly expendi...

Posted in: Mathematics | Date: 23/08/2017

employee-1: Let the monthly income be 3x and monthly expenditure be 5y employee-2 Let the monthly income be 5x and monthly expenditure be 9y employee-1: Savings= 3x-5y (income minus expenditure) employee-2: Savings= 5x-9y (income minus expenditure) Therefore 3x-5y=5x-9y=300-(I) (both saves Rs 300 per month) By solving we get 2x=4y or x=2y. Substituting value of x in terms of y in eq-1 we get 3(2y)-5y=300 or y=300. Therefore x=600 Ans: Monthly income of first employee=3x=3(600) =Rs 1800.

• ## Question: The polynomials P(x) = x3 - 6x2 + ax - 6 and Q(x) = x3 + (5 - a) x2 + 12x - 8 le...

Posted in: Mathematics | Date: 23/08/2017

Given P(x)=x3 - 6x2 + ax - 6 and Q(x)=x3 + (5-a)x2+12x + 8 leave the same remainder when divided by x - 2. By remainder theorem, if f(x) is divided by (x − a) then the remainder is f(a) Here when P(x) and Q(x) are divided by (x − 2) the remainders are p(2) and Q(2) respectively. Also given that P(2) = Q(2) → (1) Put x = 2 in both P(x) and Q(x) [Zero of the linear polynomial (x-2)=2] Hence equation (1) becomes, 2^3-6(2)^2+a(2)-6= 2^3+(5-a)(2)^2+12(2)-8 or 2a-22=44-4a or 6a=66 or a=11 Ans: Value of a is 11

• ## Question: A charge having magnitude Q is divided into two parts q and (Q – q), which are...

Posted in: AIEEE | Date: 23/08/2017

Electrostatic (repulsion) force between these two charges "Q" and "Q-q" has magnitude F=k(q)(Q−q)/r2=−k(q2−Qq)/r2 here Q and r are constant so for maximum force we have to differentiate the force "F" w.r.t "q" dF/dq = k/r2 [Q -2q] For maximum force dF/dq=0 Therefore Q-2q=0 or 2q=Q Hence the repulsion force will be maximum when q/Q =1/2

• ## Question: If 18 g of glucose is added to 178.2 g of water, then what will be the vapour pr...

Posted in: Chemistry | Date: 23/08/2017

Molecular mass of water =2×1+1×16=18g=2×1+1×16=18g For 178.2g of water nA=9.9 Molecular mass of glucose =6×12+12×1+6×16=180g=6×12+12×1+6×16=180g For 180g of glucose nB=0.1 XB=0.1/(0.1+9.9)=0.01 XA=0.99 For lowering of vapour pressure, By using the formula for colligative property P=P0AXA=P0A(1−XB) P=760(1−0.01) =760−7.6 =752.4 torr

• ## Question: A 175 m long train is travelling along a straight track with a velocity of 72 km...

Posted in: AMIE | Date: 24/08/2017

The distance bird has to travel is equal to the length of the train.i.e 175 m. Since the bird is flying parallel and opposite to the direction of the train the relative velocity will be the velocity of train plus velocity of bird = 72+18=90 km/hr=25m/s. Time taken by the bird to cross the trian= 175m/25m/s= 7 secs

• ## Question: The main door of Johns house is 2 metres broad. He usually opens it in morning ...

Posted in: Physics | Date: 25/08/2017

The force used by John on the door was 50N, at a distance 1.0m from the pivot point;i.e. hinges of the door. (since the door is 2m wide and he opens it by applying the force at the middle of the door) Since John hit the door perpendicular to its plane, the angle between the door and the direction of force was 90 degrees. Since ţ(torque) = r x F = r F sin(90) where r is the distance of the point of application of force from the pivot point, then the torque on the door was: ţ = (1.0m) (50N) sin(90) = 50 N m Farther from the hinge, less force is required to open the door. So if John opens the door at the edge then he needs to apply minimum force. F1Xr1=F2xr2 or (1.0m) (50N)=F2X (2.0m) or F2=25N The minimum force need to be applied for opening the door is 25N

• ## Question: A cistern can be filled by pipes A and B in 12 minutes and 16 minutes, respectiv...

Posted in: Bank PO | Date: 25/08/2017

Pipes A and B can fill the tank in 12 minutes and 16 minutes respectively. Therefore, in 1 minute, pipe A can fill 1/12 parts of the tank and pipe B can fill 1/16 parts of the tank Pipe C can empty the tank in 8 minutes. Therefore, in 1 minute, pipe C can empty 1/8 parts of the tank Net part filled by Pipes A,B,C together in 1 minute= 1/12+1/16-1/8=1/48 When all the taps are opened at the same time, 1/48 parts of the tank can be filled in 1 minute. i.e., the whole tank can be filled in 48 minutes

• ## Question: A stone of mass 200 g is tied to the end of a 1 m long string. Holding the strin...

Posted in: AIEEE | Date: 25/08/2017

The centripetal force acting on the stone. F = ma = mv2/r = [0.2 x 10^2] / 1 = 20 N

• ## Question: A solution of colourless salt H on boiling with excess NaOH produces a non-flamm...

Posted in: AIEEE | Date: 26/08/2017

The colourless salt (H) is either ammonium nitrate(NH4NO3) or ammonium nitrite (NH4NO2) When boiled with NaOH it will produce ammonia gas -NH3 Case-1 NH4NO3+NaOH→NaNO3+NH3↑+H2O When zinc is added to the same solution further ammonia will be produced 7NaOH+NaNO3+4Zn→4Na2ZnO2+NH3↑+2H2O Case-2 NH4NO2+NaOH→NaNO2+NH3↑+H2O 3Zn+5NaOH+NaNO2→3Na2ZnO2+NH3↑+H2O

• ## Question: I found a sample of 100 g of water contains 0.025 g of chlorine. What will be th...

Posted in: AMITE | Date: 26/08/2017

1 g/L = 1000 ppm; 1 ppm = 0.001 g/L 100 gm water=100ml of water .025 gm chlorine in 100 ml water = .0025gm chlorine per litre= 2.5 ppm concentration of chlorine will be 2.5 ppm

• ## Question: A baseball team, which played 60 games, won 30% of its games played. After a phe...

Posted in: Bank PO | Date: 27/08/2017

Number of matches won by the team in June: 30% of 60 = 18 After a phenomenal winning streak the average is 50% Assuming the team played x matches continuously and won all of them to achieve an average winning percentage of 50%. So total matches played by the team = (60+x) Total matches won by the team = (18+x) Total matches won = 50% of Total matches played Therfore (18+x)/(60+x)=0.5 (50% in fraction)=1/2 or 36+2x = 60+x or x = 24 The team has won 24 games

• ## Question: A bullet of mass 20 g moving with 600 m/s collides with a block of mass 4 kg han...

Posted in: AMIE | Date: 27/08/2017

The mass of the bullet,m1 =20g = 0.020 kg Mass of the block. m2 =4.0 kg Initial velocity of the bullet before collision, u1 =600 m/s Initial velocity of the block, u2 = 0 Velocity of the bullet after collision,v1 Velocity of the block after collision,v2 According to the conservation of linear momentum, m1u1+m2u2=m1v1+m2v2 0.02×600+4x (0)=0.02v1+4v2 --------- (eq1) Since the block rises by 0.2 m after collision and by applying law of conservation of energy, the kinetic energy of the bullet before hitting is equal to change in the potential energy of the block plus the kinetic energy of the bullet after the collision Here, (v2)^2-(u2)^2=2gh (change in the potential energy of the block) or v2= √2x10x0.2, v2=2m/s By substituting value of v2 in eq-1 we get ∴ 0.02×600=0.02v1+4×2 ⇒ 0.02v1=12−8 ⇒ v1=4/.02 ⇒v1=200m/s The velocity of the bullet when it comes out is 200m/s

• ## Question: A student forgot to add the required liquid to a round bottom flask at 25oC. He ...

Posted in: AIEEE | Date: 27/08/2017

Let the volume of the round bottomed flask be V1 Then, the volume of air inside the flask at 27° C is also V1(since no liquid added in the flask) Now, T1 = 25°C = 298° K T2 = 327° C = 600° K According to Charles’s law, V1/T1 = V2/T2 => V2 =V1T2/T1 = V1(600/298) = 2.013 V1 Therefore, volume of air expelled out = 2.013 V1 – V1 = 1.013 V Hence, percentage of air expelled out = (1.013)/(2.013)x100 = 50.32%

• ## Question: What will be the flocculation value of HCl for the colloid if the coagulation of...

Posted in: AMIE | Date: 28/08/2017

0.73 g of HCl=0.73/36.5=0.02 mole of HCl=20 millimoles of HCl 200 mL of the solution needs 20 millimoles of HCl for coagulation Thus, 1000 mL of the solution will require 5x 20 millimoles of HCl for complete coagulation = 100 millimoles so, by definition, flocculation value of HCl for the given colloid= 100

• ## Question: The population of a village decrease by 10% per 3 year. If Present population is...

Posted in: Mathematics | Date: 28/08/2017

Present population of the town =240,000 ∴ The population after 6 years will be 240,000 x 90x90/(100x100)= 194,400 Let the population before 6 years be 'p" ∴ px90x90/(100x100)=240,000, p=296,297 population before 6 years was 296,297

• ## Question: A parallel beam of light travelling in water (refractive index = 4/3) is refract...

Posted in: AIEEE | Date: 28/08/2017

Refraction at first surface u=∞;μ1=4/3; μ2=1; Radius of curvature=+2 Using equation 1/v1−(4/3)/(−∞)=(1−4/3)/(+2) V1=−3(2) V=−6 Negative sign indicates that the image is virtual and is on the same side as the object at a distance 6 mm from the first surface For refraction at second surface, the first image serves as the object which is at a distance of 6 mm +4 mm = 10 mm from the second surface μ2=4/3; μ1=1 u=−10; Radius of curvature=−2 ∴(4/3)/v2−1/(−10)=(4/3−1)/(−2) ∴4/3v2−1/(−10)=(4/3−1)/(−2) V2=-5 The final image is at a distance 5 mm from the second surface towards the left of the second surface. i.e. the final image is formed at a distance of 1 mm from the first surface

• ## Question: When a metallic surface is illuminated by a light of wavelength , the stopping p...

Posted in: AMIE | Date: 28/08/2017

According to Einstein's explanation of photoelectric emission, a photon of energy 'E' performs two operations: 1. Removes the electron from the surface of metal 2. Supplies some part of energy to move photo electron towards anode Since minimum amount of energy to remove electron from a surface is equal to work function, we can write Einstein equation as: Energy Supplied = Energy Consumed in ejecting an electron + maximum Kinetic energy of electron E= work function (W) + KEmax, So we can rewrite the formula as hν−W=1/2mv2(max) =eVo Here h is Plank's constant, ν is the frequency of the incident radiation, W is the work function, m is the mass of the emitted electron, v(max)is the speed of the emitted electron, e is the charge of the electron and Vo is the stopping potential and λ is the wavelength of the incident radiation. Using the wavelength of incident radiation the equation can be written as hc/λ−W=eVo or, hc/λ=W + eVo In the first case with wavelength 1λ and stopping potential 3V, we get, hc/1λ =W+ e(3V)-----(1) In the second case wavelength is 2λ and stopping potential 1v, we get, hc/2λ =W+ e(V) -----(2) Multiplying second equation by 2 we get, hc/λ=2W+2eV --------(3) Now, Substituting (2) in(1) , we get, 2W+ 2eV = W + 3 eV; or W=eV Substituting it in eq-3 we get, hc/λ=2W+2W; hc/λ = 4W But we can write Work function W = hc/λ0 where λ0= threshold wavelength hc/λ= 4 hc/λ0 or λ0= 4λ Threshold wavelength is 4λ

• ## Question: A straight horizontal conducting rod of length 0.5 m and mass 50 g is suspended ...

Posted in: Physics | Date: 29/08/2017

Length of the rod, L = 0.45 m Mass suspended by the wires, m = 50 g = 50 × 10 – 3 kg Acceleration due to gravity, g = 10.0 m/s2 Current in the rod flowing through the wire, I = 5.0 A B= magnitude of magnetic field (Tesla, T) Tension in the wire will be zero only when magnetic field (B) is equal and opposite to the weight of the rod, (ignoring weight of the wire), ∴ BIL=mg or B= mg/IL= (50 × 10 – 3 × 10)/ (5 × 0.45) = 0.22T The magnetic field should be 0.22T

• ## Question: Harpreet drives a car at the speed of 16 km/h, but stops for 8 minutes to take r...

Posted in: Bank Clerical | Date: 29/08/2017

Time taken by Harpreet to cover 128 km distance = t motion + t rest= 128/16 + 5(8)= 8 hrs + 40 minutes= 8 2/3 hour Harpreet will take 5 breaks of 8 minutes each to cover 128 km

• ## Question: An electrical refrigerator extracts 2000 calories from ice trays. If its coeffic...

Posted in: AIEEE | Date: 29/08/2017

COPcooling=Q/W Q is the heat removed from the cold reservoir. W is the work done, COP is the co-efficient of performance W= Q/COP= 2000/4= 500 calories Work done by electric motor is 500 calories

• ## Question: Radius of one arm of a hydraulic lift is four times the radius of the other arm....

Posted in: AIEEE | Date: 30/08/2017

Pascal's principle, for the two pistons, implies F1A2=F2A1 where A1 and A2 are cylinder areas. A1= πr2 and A2=π(4r)2 F1= F2A1/A2 Now F2=mg= 100 x 9.8 (assuming g=9.8 m/s2) or F1= (100 x 9.8 x πr2)/16πr2 = 61.25 N

• ## Question: A body of mass M kg is on the top point of a smooth hemisphere of radius 5 m. It...

Posted in: AMITE | Date: 30/08/2017

The block slides off when the normal force is zero; By applying the formula mv2/R= mg cosθ or v2/R=gcosθ or cosθ= 5x5/5x10 or cosθ=1/2 θ=60 The angle made by the radius vector with the vertical will be 60 degree

• ## Question: An ellipse intersects the hyperbola 2x2 – 2y2 = 1 orthogonally. The eccentrici...

Posted in: AMIE | Date: 30/08/2017

If the ellipse intersects the hyperbola orthogonally, their foci will coincide equations of the ellipse & the hyperbola be x2/a2+y2/b2=1and x2/A2−y2/B2=1 respectively. Rewriting the hyperbola equation 2x^2-2y^2=1 in the x^2/A^2 form we get A^2=1/2 or A=1/√2 The eccentricity of the hyperbola E=√(A2+B2)/A=√2 and the foci will be (ae,0) for a parabola and (AE,0) for a hyperbola. As the point coincdes, ae=AE=1 e= 1/√2 (e is reciprocal of E) ∴ a= √2 or a^2=2 For ellipse b2=a2(1−e2) or b=1 substituting the values we get ellipse equation as x^2/2 + y^2/1=1

• ## Question: Let A and B be two distinct points on the parabola y2 = 4x. If the axis of the p...

Posted in: Mathematics | Date: 31/08/2017

Let A(at1^2, 2at1) and B(at2^2, 2at2) be two distinct points on a parabola y^2=4x  Since the value of a=1 for the given parabola coordinates of A and B will be (t1^2, 2t1) and (t2^2, 2t2) Since the axis of the parabola touches a circle of radius r having AB as the diameter, A and B are also lying on the circle and must satisfy circle equation. Coordinates for the centre of the circle will be ((t1^2+t2^2)/2, t1+t2)) Since the axis of the parabola touches the circle, radius of the circle will be y coordinate of the centre of the circle ∴ t1+t2=±r Slope of the line joining AB will be (2t2-2t1)/(t2^2-t1^2)=2(t2-t1)/(t2-t1)(t2+t1) =2/(t2+t1)= ±2/r

• ## Question: If voltage is 'V' = (100 5) volts and current is 'I' = (10 ± 0.2) amperes, then...

Posted in: Physics | Date: 31/08/2017

%error=(exact value-approximate value)/exact value X 100

Percentage error in voltage (100 ±5)= |(100±5)|/100X100 = 5%  Percentage error in current (10 ±0.2)= |(10 ± 10.2)|/10X 100 =2% (discard any negative sign and take the absolute value) R= V/I Since R is a function two variables, the percentage error will be the sum of the percentage error of each variable

Percentage error in resistance is 5%+2%=7%

• ## Question: 75% of the students of a class passed in the exam. 55% of the passed students ar...

Posted in: Mathematics | Date: 01/09/2017

Let the number of students in the class be "s"

Number of students passed =0.75s (75% of s), Nuber of students failed =0.25s

Number of boys passed = 0.45 x 0.75s ( since 55% of passed students are girls)

Number of girls failed = 0.65 x 0.25s (since 35% of failed  students are boys)

% of passed boys over failed girls = ( 0.45 x 0.75s)/(0.65 x 0.25s)x100=27/13X100= 207.7%

• ## Question: Targeted Delivery of Government subsidies and benefits to ensure that they reach...

Posted in: Bank PO | Date: 01/09/2017

Targeted Delivery of Government subsidies and benefits (like adhaar linked transfer) will eliminate the ghost (claiming benefits under a false identity) and duplicates (same person claiming multiple benefits). Since the entire process of transfer, in an Aadhaar-enabled system, each and every transaction can be authenticated.  Suppose a beneficiary goes to a fair price shop to buy his monthly quota of ration. If the shop has a biometric authentication device connected to the entitlement database, every transaction at the shop will end up benefiting the intended beneficiaries. All that the beneficiary has to do is to authenticate whether the person is the intended beneficiary with the help of unique biometrics like finger prints or iris. Since the benefit is linked to Aadhaar number, no person with a false identity or same person cannot get benefits for the same schemes multiple times.

Since it is a better welfare delivery mechanism it will reduce the cost of the subsidy and Government will have more money to spend on other projects like improving railways infrastructure or developing ports

• ## Question: A long solenoid of cross-sectional radius R has a thin insulated wire ring tight...

Posted in: Mathematics | Date: 04/09/2017

Magnetic flux Ф= B.A ( magnetic field X Area)= Bπa^2, (a is the radius of the coil)= btπa^2 (B=bt given)

Induced emf ϵ=- NdФ/dt=-NAdB/dt=-bπa^2 (since number of turns N=1)

But  ϵ= IR hence IR- InR=bπa^2  Therefore IR(1-n)=bπa^2 or IR= bπa^2/(1-n)

dФ= Ф1-Ф2=  -bπa^2/(1-n)- (bπa^2)/2=- bπa^2 [1/(1-n)-1/2]=-bπa^2(1-n)/2(1+n)

Electric field ,  ϵ2πa= -bπa^2(1-n)/2(1+n) or ϵ=-ba(1-n)/(1+n) Since cross sectional radius a= R and Resistance is one-half is 10 times another half, n=10

ϵ=9/11Rb

• ## Question: Two particles A and B, initially at rest, move towards each other by mutual forc...

Posted in: Physics | Date: 04/09/2017

The velocity of the centre of mass will be zero. The initial velocity of the particles were zero as they were at rest so momentum will be zero.By the law of conservation of momentum, the final momentum will also be zero. as mass cannot be zero, final velocity will be zero

• ## Question: A long solenoid of cross-sectional radius R has a thin insulated wire ring tight...

Posted in: Mathematics | Date: 05/09/2017

Magnetic flux Ф= B.A ( magnetic field X Area)= Bπa^2, (a is the radius of the coil)= btπa^2 (B=bt given)

Induced emf ϵ=- NdФ/dt=-NAdB/dt=-bπa^2 (since number of turns N=1)

But  ϵ= IR hence IR- InR=bπa^2  Therefore IR(1-n)=bπa^2 or IR= bπa^2/(1-n)

dФ= Ф1-Ф2=  -bπa^2/(1-n)- (bπa^2)/2=- bπa^2 [1/(1-n)-1/2]=-bπa^2(1-n)/2(1+n)

Electric field (E)= ϵ/L(Length),  Eπa= -bπa^2(1-n)/2(1+n) or E=-ba(1-n)/2(1+n) Since cross sectional radius a= R and Resistance is one-half is 10 times another half, n=10

E=9/22Rb

• ## Question: In a family of 7 members K, L, M, N, O, P and Q, there are only two male members...

Posted in: Bank Clerical | Date: 05/09/2017

The family will be as follows K (Grandmother/Female) L(male) is K's son M(female) is L's wife  K& L has son N(male) and daughter P (female).  O (female) is N's wife and Q (female) is N's sister. So M becomes the mother-in law of K's only daughter-in-law "O".  K and N are the only males    So O is the daughter-in-law of M

• ## Question: A pair of coils has mutual inductance of 2 H. If the current in the primary chan...

Posted in: AMITE | Date: 06/09/2017

EMF induced in the secondary is e2= -MdI/dt= -(2)x10/(0.1)=200 V Induced emf in the secondary will cause a change in the flux through N loops of wire changes by dФ in a time dt,

e2=-NdФ/dt   or dФ (change in flux) = e2Xdt/N= 200X(0.1)/500=0.04 wb

Change in flux in secondary will be 0.04wb

• ## Question: Nuclear division involves replication of DNA molecules in order to duplicate chr...

Posted in: AMITE | Date: 06/09/2017

The cell cycle is divided into two major phases- Interphase and mitosis. The chromosomal DNA is duplicated during a sub portion of interphase known as the "S", or synthesis, phase.

• ## Question: A pair of coils has mutual inductance of 2 H. If the current in the primary chan...

Posted in: Physics | Date: 06/09/2017

EMF induced in the secondary is e2= -MdI/dt= -(2)x10/(0.1)=200 V Induced emf in the secondary will cause a change in the flux through N loops of wire changes by dФ in a time dt,

e2=-NdФ/dt   or dФ (change in flux) = e2Xdt/N= 200X(0.1)/500=0.04 wb

Change in flux in secondary will be 0.04wb

• ## Question: A balloon of mass m contains water of mass M. What would happen if it is complet...

Posted in: Physics | Date: 06/09/2017

From Archimedes principle, we know m-m apparent = dliq X v (v=volume of liquid). In the given problem Mass of balloon filled with water is M+m ∴ M+m -mapparent= 1XM (since density of water is 1 and volume of liquid in the balloon will be M)

m apparent = m+m-M=m  Apparent mass of balloon with water in it when completely immersed in water will be m(loss of weight of balloon = weight of water displaced

• ## Question: In a sample of radioactive material, what fraction of the initial number of acti...

Posted in: Physics | Date: 07/09/2017

Nt/N0=(1/2)^t/T1/2=(1/2)^1/2=1/√2

where Nt is the number of undisintegrated atoms after time t and N0 is the initial number of atoms

• ## Question: Two identical thin rings, each of radius R, are coaxially placed at a distance R...

Posted in: Physics | Date: 07/09/2017

Work done in an electric field W=q ΔV where q is the charge and ΔV is the electric potential

W=-q(V1-V2)

The electric potential (V) produced by a point charge with a charge of magnitude Q, at a point a distance r away from the point charge, is given by the equation: V = kQ/r, where k is a constant with a value 1/4πϵ

Potential at the centre of ring 1 is V1= Q1/kR + Q2/k √2R  ( The distance from charge Q2 is the hypotenuse of right angle triangle with base=height=R) ∵potential of two charges must be added

Potential at the centre of ring 2 is V2= Q2/kR + Q1/k √2R

∴ W= q(V2-V1)= q/k[(Q2/R + Q1/√2R ) – (Q1/R- Q2/√2R)]= q/kR[(Q2-Q1)-1/√2(Q2-Q1)]=q/K√2R(Q2-Q1)( √2-1)

W = q/4 π ϵ√2R(Q2-Q1)( √2-1)

• ## Question: A ball moves at 120 metres per second and strikes an object in three seconds. If...

Posted in: Physics | Date: 07/09/2017

d(distance) = SXt (speed x time)

The distance traveled by the ball is 120 X 3 =360 m If it moves at 100m/s it will take 360/100=3.6 sec to hit the same object

• ## Question: A bomber plane is moving horizontally with a speed of 500 m/s and a bomb release...

Posted in: Physics | Date: 07/09/2017

When the bomb is dropped, the horizontal component of the velocity Vh= 500 m/s

The vertical component of initial velocity Uv=0 and the vertical component of final velocity

Vv=Uv+gt= 0+ 10(10)=100 m/s

Let the angle of the bomb with horizon be Ф ∴ tan Ф=vertical velocity/horizontal velocity= Vv/Vh=100/500=1/5

Ф= tan^-1(1/5)

• ## Question: A steel and a copper wire have the same length, but the diameter of the steel wi...

Posted in: Physics | Date: 08/09/2017

Length of steel wire=length of copper wire=L Dimater of steel wire=2X Diameter of copper wire

∴ Area of cross-section of steel wire =4 X Area of cross section of copper wire As=4Ac

Change in length of steel wire ΔLs Change in length of copper wire = ΔLc

Force applied in both cases = F

Young modulus of steel wire Ys= (F/As)(L/ ΔLs)

Young modulus of copper wire Yc= (F/Ac)(L/ ΔLc)

Ys/Yc=2/1=( FXLXAcX ΔLc)/(FXLXAsX ΔLs)= ΔLc/4 ΔLs

∴ ΔLs/ ΔLc=1/8 Elongation ratio steel:copper=1:8

• ## Question: There are two circles. AB is diameter of the largest circle, P and Q are centres...

Posted in: Mathematics | Date: 08/09/2017

The small circle with centre Q will touch the big circle at B and M (M will be the centre of the big circle) Radius = AB/2

Radius of small circle with centre Q=AB/4

• ## Question: A step-down transformer is employed to reduce the main supply of 220 V to 11 V. ...

Posted in: Physics | Date: 08/09/2017

Efficiency= Power output/power input X 100= (11x90x100)/(220X5)= 90%

• ## Question: A constant voltage is applied between the two ends of a metallic wire. Some heat...

Posted in: AMITE | Date: 08/09/2017

H = I2Rt   If voltage and t is constant then H α R  where R will vary with length and cross section area.

So the heat will be doubled if length and the radius of the wire is doubled

• ## Question: A manometer connected to a closed tap reads 4.5 × 10 5 Pa. When the tap is open...

Posted in: AMITE | Date: 08/09/2017

From Bernoulli's theorem, we know

1/2V^2=(P1-P2)/ρ  where V is the velocity of fluid( water in this case) P1 & P2 are the pressures and ρ is the density of the fluid

V^2= 2(4.5 X 10^5-4.0 X 10^5)/10^3 m/s = 2 x 0.5 x 10^2=10^2 m/s

∴ V=10 m/s

• ## Question: What percent of sample of nitrogen must be allowed to escape if its temperature,...

Posted in: AMITE | Date: 08/09/2017

From Ideal Gas Law we know PV = nRT or n = PV/RT

p1= 3 atm V1=1.65 L  T1= (273+220) =493K  P2=0.7 atm,  T2= (273+110)=383K, V2= 1.0L

percent nitorgen to be released= (n1-n2)/n1X100=(1-n2/n1)X100

= [1- (0.7X1X493)/(3X1.65X383)]X100= 81.7%

• ## Question: Let PQR be a right-angled isosceles triangle, right-angled at P (2, 1). If the e...

Posted in: AIEEE | Date: 09/09/2017

Equation of the line QR= 2x+y=3 or y= -2x+3 so the slope of the line will be m1 = (-2)

In the Δ PQR, PQ=PR ∴ <PQR=<PRQ=45  Since the  angle between QR and PQ=45

Tan 45= (m1-m2)/(1+m1m2) where m2= slope of PQ

1= (-2)-m2/1+(2)m2 or m2=3 and, Point P(2,1) is common to both  PQ and PR

Eqn of line PQ= y-1/(x-2)=3 or 3x-y-5=0

Since PQ and PR are perpendicular to each other  m2xm3=-1 (m3  is the slope of  PR)

m3= -1/3 Eqn of line PR= y-1/x-2=-1/3 or 2x+3y-7=0

∴ Joint eqn of PQ and PR will be (3x-y-5)( 2x+3y-7 )=0 Multiplying it we get

6x^2-3y^2+7xy-31x-8y+35=0 which will represent the pair of lines PQ and PR

• ## Question: Two charges are separated by a distance d. If the distance between them is doubl...

Posted in: AMITE | Date: 09/09/2017

q1--------d--------------q2 .

A                            B

The electric potential energy of the system V1=q1q2/kd  When the distance between the charges are doubled the new potential will be V2= q1q2/k2d Change in the potential ΔV= V1-V2= q1q2/k(1/d-1/2d)= q1q2/2kd

• ## Question: A steel scale measures the length of a copper rod as L cm when both are at 20°C...

Posted in: AMIE | Date: 10/09/2017

At  20°C, Length of copper rod= Measure in the scale=L

At 21°C Lenght of copper rod will be L+ ΔL= L+ LαΔT  = L+Lα    (ΔT=21°-20° =1) α is the coefficient of linear expansion of copper

At 21°C Length of the steel scale will be L+ ΔL=  = L +Lβ   where β is coefficient of linear expansion of steel

Considering the value of α at 20°C, as 17X10^-6 and β as 12 X 10^-6

At 21°C, the ratio of the length of the copper rod to the measure of the scale will be 1.000017/1.000012=1.000005

So the scale will measure the steel rod as 1.000005L

• ## Question: An elevator car whose floor to ceiling distance is equal to 2.7 m starts ascendi...

Posted in: AIEEE | Date: 10/09/2017

Floor to ceiling distance of the elevator= 2.7m

Acceleration of the elevator = 1.2 m/s^2 upwards

Relative acceleration  of the bolt = (g+a) = 9.8+1.2 = 11m/s^2. ( the acceleration has to be added when the elevator is going up because it is accelerating against downward gravitational pull)

Let time t to reach the distance of 2.7 m

U = 0 s = 2.7m , a = 11 m/s^2

From the second equation

S = ut+1/2 at^2

S = ½ *11* t^2

5.4 = 11 t^2

t = 0.7 sec time taken to hit the floor will be 0.7s

• ## Question: Help me to know how much heat is released when 100 mL of 0.1 M NaOH is completel...

Posted in: AIEEE | Date: 10/09/2017

The heat of neutralization between a strong acid and a strong base is -57.62kJ/mol

1 M of  NaOH will be exactly neutralised with 1 M of HCl.

∴ 0.1M of NaOH will neutralize 0.1 M of HCl  to give   57.62kJ x 0.1 = 5.76 KJ of heat

• ## Question: A coil of metal wire is kept stationary with its plane perpendicular to a unifor...

Posted in: Physics | Date: 10/09/2017

When a charged particle is moving through a magnetic field, a magnetic force acts on it. –This force has a maximum value when the charge moves perpendicularly to the magnetic field lines. –This force is zero when the charge moves along the field lines. So when current is passed through the coil a magnetic field will be induced in the coil. The direction of the force can be found by applying the "Right hand rule" and the intensity of the field can be calculated from Bio-Savart's Law

• ## Question: If 150 kJ of energy is needed for a man to walk a distance of 1 km, then how muc...

Posted in: AMITE | Date: 10/09/2017

For walking 1 km the man needs 150KJ of energy. To walk 5 kms he needs 150X5=750 KJ energy.

If only 30% of energy is available for muscular work, the total energy needed will be 750/30X100= 2500KJ

1 mole of glucose produces 3000 KJ. Then for producing 2500 KJ, 5/6 mole of glucose =5/6X180 =150 gms of glucose will be needed (assuming molecular weight of glucose=180 gms)

• ## Question: A simple pendulum consists of a sphere of mass m suspended by a thread of length...

Posted in: Physics | Date: 10/09/2017

The length of the pendulum is "l"  and mass  "g". suspended vertically in an electric field E and carrying a charge q

Gravitational force downward on the pendulum =mg Electric force upward on the pendulum = Eq

Since the electrostatic force is less than gravitational force the net force downward on the pendulum = (mg-Eq)

Net acceleration of the pendulum (mg-Eq)/m= (g-Eq/m)

Time period T =2π√(l/(g-Eq/m)

• ## Question: At constant temperature, volume of a gas increases by 18% on changing its temper...

Posted in: Chemistry | Date: 10/09/2017

V1/T1=V2/T2   V1/(27+273)=1.18V1/(27n+273) or V1/300= 1.18V1/(27n+273)

or 27n + 273 = 354 or 27n =81 or n= 3

• ## Question: A bird in air looks at a fish vertically below it inside water. X is height of t...

Posted in: AIEEE | Date: 11/09/2017

Height of the bird in air=X

Depth of fish in water =Y

The fish is viewing the bird in air from a denser medium water of refractive index μ (assume as the data is missing).

If the bird is viewed normally by the fish then

μ= (Apparent depth in air)/(Real depth in air) or Apparent depth in air= μX

Since the fish is Y m below, it will see the bird at a distance(μX +Y) from it

• ## Question: Horse hemoglobin contains 0.335 % iron. A 1% solution of the hemoglobin has an o...

Posted in: Chemistry | Date: 11/09/2017

Percentage of Iron = 0.335% molecular weight of haemoglobin

Weight of Fe present = (0.335/100) ×16716= 55.9 gm

Molecular weight of approx 55.9  Therefore one molecule of iron weighs 55.9gm Therefore, 55.9/55.9 = 1   Molecular weight of iron= atomic weight of iron

Hence, 1 atom of iron is present in one molecule of haemoglobin.

• ## Question: R1 is the rate of a simple reaction 2NO + O2 2NO2. If the volume of the reaction...

Posted in: Chemistry | Date: 12/09/2017

From Law of mass action, we know Rate of reaction

R1=k[NO]^2[O2] where k is the rate constant.

When the volume of the vessel is doubled, the concentration of the reactants will be halved.

New rate R2= k(1/2[NO]^2)(1/2[O2}= 1/8(R1)

By doubling the volume, the rate of reaction will become 1/8th of the previous rate

• ## Question: A small trolley of mass 2 kg resting on a horizontal frictionless turntable is c...

Posted in: Physics | Date: 13/09/2017

Mass of trolley m=2kg., angular frequency ω= 10 rads/sec

When the turntable is rotated, the length of the spring becomes the radius of the circle along which the trolley moves. So r= 40 cm=0.4m

When the turntable is rotated, the tension in the spring is equal but opposite in direction to the centripetal force

∴ T=mv^2/r= mrω^2= 2X 0.4 X (10)^2 =80N

Extension produced in this spring =40-35=5 cm =,05m

Force constant of spring = Force/extension = 80/.05 N/m=1.6 X 10^3 N/m

• ## Question: A person measures the time period of a simple pendulum inside a stationary lift ...

Posted in: AIEEE | Date: 13/09/2017

The time period of the pendulum in the stationary lift is T1=2 π √l/g  where l is the length of the pendulum and g is the acceleration due to gravity

When the lift start accelerating upwards

From  Newton's 2nd Law we know (ΣF=ma) acting on the pendulum. The overall acceleration of the pendulum is upward (with the lift). So ma is positive (upward). The only external forces acting on the pendulum are the force of gravity acting down (-W=-mg) and the supporting Normal Force FN upward on the pendulum

. So ΣFN=ma(net)=-ma –mk (k=acceleration of the lift)_

∴a=−(g+k)   In the problem it is given k= g/3

a=g+g/3=4g/3 ignoring the direction of the force

Let the new time period be T2 when the pendulum is accelerating with lift

T1/T2= √ [g/(4g/3)] or T2=T1√3g/4g or T2= √3/2T1

• ## Question: A hollow metal sphere of radius 5 cm is charged such that the potential on its s...

Posted in: AIEEE | Date: 13/09/2017

The potential at any point inside the sphere is the same as the potential at the surface ie 10V

• ## Question: A small ball is pushed from a height 'h' along a smooth hemispherical bowl. With...

Posted in: Physics | Date: 13/09/2017

When the ball is at h the PE1 of the ball is mgh

When the ball is pushed with a velocity v it  reaches the bottom with KE1=1/2mv^2

Then by inertia the ball travels upto R when its PE2= mgR and the velocity =0 KE2=0

From law of conservation of energy

PE1+KE1=PE2+KE2 or mgh+1/2mv^2=mgR+0 solving it we get V= √2g(R-h)

• ## Question: Let L1 be a straight line passing through the origin and L2 be the straight line...

Posted in: AIEEE | Date: 18/09/2017

Solution enclosed

• ## Question: The triangle PQR is inscribed in the circle x2 + y2 = 25. If Q and R have coordi...

Posted in: AMITE | Date: 18/09/2017

Solution enclosed

• ## Question: When a car moves on a road with uniform speed of 30 km/h, then what would be the...

Posted in: Physics | Date: 18/09/2017

As the car is moving at a constant velocity, its acceleration is zero. According to Newton’s second of motion the net force F=ma (mass of the car X acceleration of the car) Since a=0

Net force acting on the arc is zero.

• ## Question: The number of electrons to be put on spherical conductor of radius 0.1 m, to pro...

Posted in: AIPMT | Date: 18/09/2017

We can find the electric field created by a point charge by using the equation E = kQ / r2 . (where K= 9 X 10^9 N m2/C2)

and Q=ne ( where n is the number of electrons and e is the charge of one electron = 1.6 X10^-19 C)

Therefore n= Er2./Ke=( 0.036 X 0.1 X 0.1)/(9 X 10^9 X 1.6 X10^-19 )= 2.5 X 10^5

• ## Question: How should I calculate the equivalent resistance between P and Q? Help me to so...

Posted in: AIPG Exam | Date: 18/09/2017

For the above circuit, we get a balanced Wheatstone bridge, because 3Ώ/4Ώ=6Ώ/8Ώ. Hence the point R and S will be at the same potential. Hence no current will flow through the resistance 7Ώ. The network is therefore equivalent to two resistances (3+4)Ώ and (6+8)Ώ joined in parallel. Equivalent resistance R will be 1/R=1/7+1/14

∴ R= 14/3= 4.67Ώ

• ## Question: An electron moves through a small distance in uniform electric field. The magnit...

Posted in: Physics | Date: 19/09/2017

solution attached

• ## Question: How should I find the greatest number that will divide 90 and 107 and leave rema...

Posted in: AMITE | Date: 19/09/2017

Since the number that will divide 90 leaving a reminder 2 and 107 leaving a render 3, the number should be the H.C.F of the numbers (90-2)=88 and (107-3) = 104

88= 8 X 11

104 = 8 X 13

HCF= 8

∴The greatest number which divides 90 and 107 leaving remainder 2 and 3 respectively is 8.

• ## Question: A child is swinging a swing. The minimum and the maximum heights of swing from e...

Posted in: AIEEE | Date: 19/09/2017

solution

• ## Question: When the radius of earth is reduced by 1% without changing the mass. then what ...

Posted in: AIEEE | Date: 19/09/2017

From Newton's law, we can derive Force, F=mg=GmM/r2 (where g is the acceleration due to gravity, G is universal gravitation constant, m is mass of the body and M is mass of earth)

∴ g= GM/r^2  Hence g/gnew= r^2/rnew^2 eqn -1

Since the radius of earth is reduced by 1%, rnew =0.99r

and rnew^2=(0.99r)^2=0.98r^2

Putting it in eqn 1 we get g/gnew=r^2/0.98r^2, gnew=gX(1.02)

∴ Percentage change in g = (1.02g-g)/gX100= 2%

Acceleration due to gravity will change by 2% for 1% reduction in earth's radius

• ## Question: A body of mass 5 kg is moving in a circle of radius 1 m with an angular velocity...

Posted in: Physics | Date: 19/09/2017

Centripetal Force F=mω2r  m=5kg, ω=2 rad/s r=1m Substituting the values we get

F=5X4X1= 20N

• ## Question: The speed of boat is 5 km/h in still water. If it crosses a river of width 1 km ...

Posted in: Bank PO | Date: 19/09/2017

solution

• ## Question: How is the interference pattern in Young’s double-slit experiment affected if ...

Posted in: Physics | Date: 19/09/2017

The separation between two consecutive bright and dark fringes is same and is called the fringe width β

β = λD/d where λ is the wavelength of the light, D is the slit screen distance and d is the distance between the slits.

So fringe width is directly proportional to wavelength λ and the slit screen distance D and inversely proportional to distance d between the slits

Keeping all other factors constant

if the yellow light is replaced with red light since  λr > λy (wavelength of red light greater than the wavelength of yellow light) the fringe width will increase

• ## Question: Half-lives of two radioactive substances A and B are respectively 20 min and 40 ...

Posted in: Physics | Date: 19/09/2017

t1/2 of A= 20 mins and B= 40 mins

t=80 =4tA=2tB

After 80 mins, number of nuclei of A remaining is N0/2^4=N0/16 (where No is the initial number of nuclei of A, B)

After 80 mins, number of nuclei of B remaining is N0/2^2=N0/4

∴ Ratio of nuclei remaining of A and B = 1:4

• ## Question: The locus of the mid-point of a chord of the circle x2 + y2 = 4, help me to find...

Posted in: AIEEE | Date: 19/09/2017

The question needs to be corrected as "Find locus of midpoint of chord of the circle x2 + y2 = 4 subtending a right angle at the origin" Solution attached

• ## Question: The coefficient of x in the quadratic equation ax2 + bx + c = 0 was wrongly take...

Posted in: AMITE | Date: 19/09/2017

Wrong quadratic equation roots are  (-2) and (-15) and b= 17

Sum of the roots  (-2) + (-15)= 17/a or a=1 Product of the roots are (-2) X (-15) =30 =c/a ∴ c=30

For correct equation b=13 Sum of the roots =-13/1=-13  Product of the roots = 30/1=30

So the roots are (-13+/-√(13^2-4(1)(30))/2(1) = (-13 + 7)/2 and (-13-7)/2 = (-3) and (-10)

Roots of correct equations are -3 and -10

• ## Question: An aeroplane moving horizontally with a speed of 720 km/h drops a food packet wh...

Posted in: Physics | Date: 19/09/2017

When the food packet is dropped the vertical component of its velocity is zero and horizontal component is 720 km/hr.

Let the time taken by the food to reach ground be "t"

dvert = ut +1/2gt^2 or  396.6= (o)t + 1/2(9.8)t^2 or t^2= (396.9 X 2)/9.8= 81 ot t=9

dhor = vhor X t= (720 X 9 X 10^3)/3600= 1800

The food packet will take 9 secs to reach the ground and horizontal range is 1800 m

• ## Question: In photohalogenation reaction of an organic compound, the radiation of wavelengt...

Posted in: GATE Exam | Date: 20/09/2017

D is the correct option

• ## Question: A substance when dissolved in water at 10-3 M absorbs 10% of an incident radiati...

Posted in: GATE Exam | Date: 20/09/2017

The options need to be checked in the Question. Option A should be 0.0218 mol/dm3

• ## Question: A photon collides with a stationary hydrogen atom in ground state inelastically....

Posted in: CET | Date: 20/09/2017

Option C is the correct option

• ## Question: A man running around a race course notes that the sum of the distances of two fl...

Posted in: AMITE | Date: 20/09/2017

The race course will be an ellipse with flag posts as its foci. Major Axis a= 1/2 X 10 =5, Minor axis b= 3 (By applying Pythagoras theorem)

Area of the path enclosed =π X5 X3=15π=47.12 m2

• ## Question: Two small spheres of masses M1, and M2 are suspended by weightless insulating th...

Posted in: AIPG Exam | Date: 21/09/2017

Option C is the correct option

• ## Question: The coefficient of thermal conductivity of copper is 9 times that of steel. In t...

Posted in: AMITE | Date: 21/09/2017

Option A is the correct option

• ## Question: To get an output y = 1 from the circuit shown, what must be the inputs of A, B a...

Posted in: CET | Date: 21/09/2017

Cannot be answered as the circuit diagram is missing

• ## Question: What would be the equivalent resistance between the points A and B will be (each...

Posted in: Physics | Date: 21/09/2017

Option B is the correct option

• ## Question: The moment of inertia of a circular disc of radius 2 m and mass 1 kg about an ax...

Posted in: Physics | Date: 22/09/2017

By applying the theorem of parallel axes moment of Inertia "I" of a body  is I=Ig + MR^2= where Ig is the moment of inertia about an axis passing through the centre of mass but perpendicular to the plane of the body plus MR^2 where M is the mass of the body and R is the distance between the axis and the centre of mass

I = 2 + 1X2^2=6 kgm2

Hence option B is the correct option

• ## Question: Two cards are drawn from a pack. The probability of getting a king and a queen w...

Posted in: Bank PO | Date: 22/09/2017

Out of pack of 52 cards one king and one queen can be drawn by(4C1)∗(4C1)=16 ways (assuming the order doesn't matter)

Out of Out of pack of 52 cards two cards can be drawn by 52C2= 1326 ways

Probability of getting a king and a queen will be 16/1326=8/663 ways

Hence option D is the correct option

• ## Question: In a material, the magnetic field intensity is H = 1200 A/m when B = 2 Wb/m2. Wh...

Posted in: GATE Exam | Date: 22/09/2017

solution

• ## Question: Light of wavelength 488 nm produced by an Argon laser is incident on a emitter o...

Posted in: AIEEE | Date: 22/09/2017

ignore earlier solution as the wrong file was attached Correct solution

• ## Question: Two charged metallic spheres of capacitances $$C_{1}$$ and $$C_{2}$$ are given c...

Posted in: AMITE | Date: 23/09/2017

solution

• ## Question: The following figure shows the phenomenon of pair production and the subsequent ...

Posted in: AMITE | Date: 23/09/2017

The direction of the magnetic field is out of the plane of the figure.

• ## Question: A toroid has a ferromagnetic core of inner radius 24 cm and outer radius 26 cm a...

Posted in: AIEEE | Date: 23/09/2017

solution

• ## Question: Which of the following errors is there, if the temperature graduations of a ther...

Posted in: AIEEE | Date: 23/09/2017

Option B. It is an instrumental error due to wrong design or wrong calibration of the thermometer

• ## Question: There are 60 students in a class. These students are divided into three groups A...

Posted in: GATE Exam | Date: 23/09/2017

Average weight of the group D cannot be determined as we do not know the average weight of each student. Data insufficient

Hence option D is the correct option

• ## Question: A computer has the following negative numbers stored in binary form as shown. Ho...

Posted in: CET | Date: 23/09/2017

solution

• ## Question: A charge of 5μC is placed at the centre of a sphere A of radius 10.0 cm. The ...

Posted in: Physics | Date: 23/09/2017

Flux Ф through the sphere is given by the relation  Ф = q/ε0 where q is the charge and

ε0  is the permittivity of the free space

The total flux through the closed sphere is independent of the radius of the sphere .

So the ratio of flux  of sphere A and B will be 1 as the flux will be equal

• ## Question: A solid conducting sphere of radius 10 cm is enclosed by a thin metallic shell o...

Posted in: Physics | Date: 24/09/2017

The question has an error. The Charge q= 20 micro coloumb and not 20 C Then option B will be the correct option

• ## Question: Deduce the amount of instantaneous power supplied to a capacitor of capacitance ...

Posted in: AIEEE | Date: 25/09/2017

The instantaneous  power for a pure capacitative circuit will be (VmXIm/2)Xcos(90)-(VmXIm/2)Xcos(2wt+90)

Average power will be zero

Please see the working for the details

• ## Question: To prepare a solution of concentration of 0.03 g/mL of $$AgNO_3$$, what amount o...

Posted in: AICEE | Date: 25/09/2017

Amount = 0.03 X 60 =1.8 g

Option A

• ## Question: The rate constant of a first order reaction at $$27^0$$C is $${10}^{-3}$$ min&nd...

Posted in: AIPMT | Date: 25/09/2017

Temperature coefficient μ =  KT+10/KT

μ=2, K27= 10^-3

2=10^-3/K17  Hence K17= 10^-3/2= 5X10^-4

Option B

• ## Question: A body measures 5N in air and 2N when put in water. What would be the buoyant fo...

Posted in: AIPMT | Date: 25/09/2017

Buoyant Force (Force with which the water is pushing up the body) = weight in air - Weight in water = 5N-2N=3N

Option C

• ## Question: A satellite of mass m is circulating around the earth with constant angular velo...

Posted in: AIPG Exam | Date: 26/09/2017

As the satellite is orbiting around earth (considering earth's orbit as circular rather than elliptical)

its centripetal force must be equal to Gravitational Force

Centripetal Force = mRoω^2= GMm/Ro^2    (ω= angular velocity of the satellite and G is the universal gravitational constant) so ω= √(GM/Ro^3)

Angular momentum of the satellite, J= mωRo^2= m√(GMRo)

• ## Question: A man of blood group ‘A’ marries a woman of blood group ‘B&rsq...

Posted in: AIPMT | Date: 26/09/2017

A man with heterozygous blood group A will have the genotype AO married to a woman with heterozygous blood group B with genotype BO

A       O

B     AB    BO

O     AO  OO

Chances of the first child having AB =1/4= 25%

• ## Question: Sara, Bula and Kamal together can finish a work in 4 days. If Sara alone can f...

Posted in: Bank PO | Date: 26/09/2017

Sara can finish the work in 12 Days. In I day she does 1/12 parts of the work

Bula can finish the work in 18 Days. In I day she does 1/18 parts of the work

Kamal can finish the work in d Days. In I day she does 1/d parts of the work

They together can complete in 4 days. In I day they can do 1/4 parts of the work

Hence 1/12+1/18+1/d=1/4 so 1/d= 1/4-1/12-1/18= 1/9

Hence Kamal can complete the work in 9 days  Option A

• ## Question: When the atomic weight of an element is 52 and the atomic number is 24 then what...

Posted in: AIPMT | Date: 26/09/2017

For any element:      Number of Protons = Atomic Number

Number of Electrons = Number of Protons = Atomic Number

Number of Neutrons = Mass Number - Atomic Number

• ## Question: Atoms may be regarded as comprising of protons, neutrons and electrons. If the m...

Posted in: AIPMT | Date: 26/09/2017

Atomic mass =number of protons +number of neutrons

In 6C12,number of Protons,Electrons: 6

Number of Neutrons: 12-6=6

Mass of neutron is halved and the electron is doubled. Mass of electron is negligible and hence it will not contribute to any change

New atomic mass = 6/3(N) +6(P)=9 Hence atomic mass will reduce by 12-9=3

Reduction is 3/12X100= 25%

Option D

• ## Question: What is the maximum number of 4f electrons, having spin quantum number 1/2?...

Posted in: AIPMT | Date: 26/09/2017

4f subshell has seven orbitals for a total of 14 electrons

ms, the spin quantum number defines the spin state of each electron. Since there are only two allowed values of spin, thus there can only be two electrons per orbital. The values of m=± 1/2  ie. 1 electron will have +1/2 value per orbitalHence 7 orbitals will have 7 electrons with ms +1/2

Option D

• ## Question: How many electrons have their spins paired in an atom of oxygen (Atomic Number 8...

Posted in: AIPMT | Date: 26/09/2017

Option D 6 electrons refer to the attached explanation

• ## Question: What is the value of an electron in a 4s orbital may have a magnetic quantum num...

Posted in: AIPMT | Date: 26/09/2017

Electrons in a particular subshell (such as s, p, d, or f) are defined by values of  (0, 1, 2, or 3).

For 4s orbital  mℓ=0

Option B

Posted in: AIPMT | Date: 26/09/2017

Wavelength of ray's in increasing order of λ

ɣ ray < X-ray <UV <IR <Microwave<Radio wave

Hence Option A i.e Radiowave will have maximum wavelength

• ## Question: If two bodies have circular path of radius r$$_1$$ and r$$_2$$ and the time take...

Posted in: Physics | Date: 26/09/2017

Angular velocity ω=θ/t Where θ=2π ؞ ω1/ω2=θ/t 1/θ/t 2=t2/t1  Since t1=t2 time taken are same

ω1:ω2= 1:1  ie same angular velocity

• ## Question:  Why is it impossible to determine the exact position and the exact en...

Posted in: AIPMT | Date: 26/09/2017

Electrons can act like wave and particle known as wave-particle duality. Heisenberg uncertainty principle states that the exact position and momentum of an electron cannot be simultaneously determined because of wave-particle duality.

Hence option C

• ## Question: What happen when The Aufbau's principle implies that a new electron will ent...

Posted in: AIPMT | Date: 26/09/2017

Aufbau principle states that the electrons will first occupy the orbitals that have the lowest energy

The order in which the electrons should be filled is 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p…..

The order of the increasing energy of the orbitals can also be calculated using (n+l) rule.

If the value of n+l for two orbitals is equal then the orbital with lower value of n will have lower energy level, hence electron will first occupy it

Option A

• ## Question: The principal quantum number of an atom is related to the----

Posted in: AIPMT | Date: 26/09/2017

The principal quantum number, n, refers to the energy level an electron  placed in and to the size of the orbital

Option A

• ## Question: A gas mixture contains O2 and N2 in the ratio of 1 : 4 by weight. How should I f...

Posted in: AICEE | Date: 27/09/2017

Option D 7:32

Ratio of oxygen: nitrogen = 1: 4= 1gm:4gm

Molecular weight of oxygen=32 and Nitrogen =28. 32 gm of Oxygen OR 28 gm of Nitrogen will contain N molecules

1gm Oxygen contains N/32 molecules of oxygen whereas 4 gms of nitrogen will contain 4N/28 molecules of nitrogen

Ratio of molecules of oxygen: molecules of nitrogen= N/32/4N/28= 7:32

• ## Question: What is the reason when alpha particles are sent through a thin metal foil ...

Posted in: AIPMT | Date: 27/09/2017

Option C

Reason: The nucleus of an atom has a relatively small diameter compared with that of the atom. So most of the space in an atom is empty. Hence the most of alpha particles can pass straight through the metal foil

• ## Question: Two balloons are filled, one with pure He gas and the other by air, respectively...

Posted in: AICEE | Date: 27/09/2017

Option B  the same in both the balloons

Reasons: Avogadro's principle states that at the same temperature and pressure equal volumes of all gases contain the same number of molecules. Both balloons are at same temperature and pressure and unit volume(=1)

• ## Question: A cylinder of mass 10 kg and radius 15 cm is rolling perfectly on a plane of inc...

Posted in: Physics | Date: 29/09/2017

(a) Force of friction = ½ ma = ½ (10 X 3.27) = 16.35N

(b).Hence, the work done is 0.

(c) The maximum allowed angle for rolling without slipping for cylinder rolling down the plane,θmax = tan-1(3µ)

= tan-1(3X0.25) = 36.86degree

Please refer to the solution below

• ## Question: If the de-broglie wavelength of a particle of mass m is 100 times its velocity, ...

Posted in: AIPMT | Date: 29/09/2017

λ = 10√(h/m)

• ## Question: A man runs across the roof-top of a tall building and jumps horizontally with th...

Posted in: AIEEE | Date: 29/09/2017

Yes, the man will be able to land on the next building

• ## Question: A car moving on a straight highway with speed of 126km/hr. is brought to stop wi...

Posted in: AMITE | Date: 29/09/2017

Initial velocity of the car U= 126 km/hr = 126 X1000/(60X60)= 35 m/s

Since the car is stopping, the final velocity= 0

(i) V^2-U^2=2aS (S=200 m given)  a= (35)^2/2(200)= -3.06 m/s2

Retardation of the car = 3.06 ms-2

(ii) V=U+at   0= 35 -3.06t or t= 35/3.06 = 11.42 s

The car will take 11.44 s to stop

• ## Question: Two light springs of force constants k1 and k2 and a block of mass m are in one ...

Posted in: AIPMT | Date: 30/09/2017

Solution

• ## Question: In a transverse progressive wave of amplitude A, the maximum particle velocity i...

Posted in: AICEE | Date: 30/09/2017

Solution

• ## Question: The concentric spheres of radii R and r have similar charges with equal surface ...

Posted in: AIPMT | Date: 01/10/2017

solution

• ## Question: Two identical capacitors $$C_{1}$$ and $$C_{2}$$ each of capacitance C are conne...

Posted in: Physics | Date: 01/10/2017

solution

• ## Question: A balloon is ascending at the rate of 4.9m/s. A pocket is dropped from the ballo...

Posted in: Physics | Date: 01/10/2017

initial velocity of the packet , u = 4.9 m/s final velocity = v m/s  height, h = 245 m   g = 9.8 m/s² time taken = t seconds h = ut + 0.5gt²    [ since u is upward it is taken as negative) 245=-4.9t + 0.5(9.8)t² ⇒245 = -4.9t + 0.5×(9.8)×t² ⇒ 245 =- 4.9t + 4.9t² ⇒ 4.9t² -4.9t -245 =0 ⇒ t² -t -50 =0  Solving it, we get  t = 7.59s 0R  t = -6.59s (discarded since time can't be negative)

v = u + gt = -4.9 +9.8(7.59) = -4.9 +74.38 = 69.48 m/s  So final velocity is 69.48 m/s downward

• ## Question: In the given figure, the capacitors $$C_1$$, $$C_3$$, $$C_4$$ and $$C_5$$ have a...

Posted in: AIPG Exam | Date: 01/10/2017

solution

• ## Question: What would be the total energy stored in the condenser system shown in the figur...

Posted in: AMITE | Date: 01/10/2017

Option C is the correct answer

• ## Question: Two organ pipes sounded together give 5 beats per second. If their lengths are i...

Posted in: AIPMT | Date: 02/10/2017

Let nA and nB be the frequency of the organ pipes A and B respectively.

We have, nA= v/4lA and nB= v/4lB  where v=vlocity of sound in air, lA is the length of the air column resonating with pipe A and lB is the length resonating with pipe B.

and nA/nB= lB/lA = 51/50 (given)       eqn .....(1)

Since both pipes together produce 5 beats per second, nA-nB = 5   eqn......(2)

By solving eqn (1) and (2) we get  nA=255 Hz and nB=250 Hz

Hence option D is the correct answer

• ## Question: A mixture contains alcohol and water in the ratio 4 : 3. If 5 liters of water is...

Posted in: Mathematics | Date: 03/10/2017

Let the volume of alcohol in the mixture be 4x liters. Since  Alcohol: water= 4:3, there will be 3x liters of water in the mixture.

Now 5 liters of water is added and the new ratio becomes 4:5

4x/(3x+5)= 4/5 by solving we get x= 5/2.

Volume of alcohol in the mixture = 4(5/2)= 10 liters. Hence option A is the correct option

• ## Question: In covering a distance of 40 km, Tushar takes 2 hours more than Ashish. If Tusha...

Posted in: Bank PO | Date: 03/10/2017

Let Tushar's speed be x km/hr and Ashish be y km/hr.

To cover 40 kms. Tushar took 40/x hrs and Asish took 40/y hrs.Since Tushar took 2 hours more than Ashish,

40/x - 40/y = 2 eqn ....(1)

If Tushar doubles his speed, then he took 40/2xhours to cover the same distance. Since he took 1 hour less than Ashish,

40/y-40/2x=1 eqn.....(2) Solving the eqns we get

x=20/3 = 6.67 and y=10. Therefore Tushar's speed is 6.67 kms/hr

• ## Question: A sum of money placed at compound interest doubles itself in 4 years. In how man...

Posted in: Bank PO | Date: 03/10/2017

Let A = amount, P = principal, r= rate of interest compounded per annum n=time in years

By using compound interest formula we get 2A= A(1+r)^4 or (1+r)^4=2 eqn...(1)

Let the amount become 8 times in 't' years Therefore 8A=A(1+r)^t or (1+r)^t= 8 =2^3....eqn(2)

(1+r) = 2^1/4= 2^3/t ∴​ ​1/4= 3/t or t =12

Option D is the correct answer

• ## Question: Which one of the below mentioned  reaction by which benzaldehyde is convert...

Posted in: AIPMT | Date: 03/10/2017

Cannizzaro reaction is a chemical reaction of benzaldehyde with potassium hydroxide to produce benzyl alcohol

2 C6H5CHO + KOH → C6H5CH2OH (benzyl alcohol) + C6H5COOK

Option B

• ## Question: According to Einstein's photoelectric equation, if the plot of the kinetic e...

Posted in: AIPMT | Date: 03/10/2017

According to the Einstein’s Photoelectric equation

Ek=hν−Ф  Ek is the kinetic energy of the electron, h is Planck's constant, ν is the frequency and Ф is the stopping potential

Compare it with equation of a straight line y = mx + c

Ek and v (frequency) are variables. The slope of the line m is plank’s constant (h).

Thus, the slope is same for all metals and independent of the intensity of radiation.

The correct option is D.

• ## Question: An atomiser is based on the application of---- Please explain me the answer.

Posted in: AIPMT | Date: 04/10/2017

Atomizers use Bernoulli's principle.The pressure inside an atomizer is relatively high. At one end of the horizontal tube is a squeeze-pump which causes air to flow through it. Squeezing of the bulb over the fluid creates a low-pressure area due to the higher speed of the air, As the pressure toward the top of the bottle is reduced, the perfume flows along the tube, drawn from the higher pressure area at the bottom which subsequently draws the fluid up.

• ## Question: A capacitor C1 is charged by potential difference V0 as show...

Posted in: AIPMT | Date: 04/10/2017

The voltage of the capacitorC1 is V0= q1/C1 and the voltage of the uncharged capacitor C2 is 0 as its charge is 0.

When the two capacitors are electrically connected then the charge will flow from higher potential to lower potential till the difference of potential ceases to exist. Let the common potential of C1 and C2 be V. Assuming no loss charge during the charge sharing process, Total charge before connection = Total charge after connection

i.e C1V0 + 0 = C1V + C2V = (C1+C2)V or V= Vo C1/(C1+C2)

Final potential V= Vo C1/(C1+C2)

• ## Question: If we move from equator to pole, then what will be the value of g? Please give m...

Posted in: AIPMT | Date: 04/10/2017

Since the Earth is flattened at the poles and bulges at the equator, an oblate spheroid the distance from Earth's center to sea level is roughly 21 kilometers (13 miles) greater at the equator than at the poles. Since the value of g varies inversely with the square of the earth's radius, the shorter radius at the pole will result in a greater value of g.

The second reason is that at latitudes nearer the Equator, the outward centrifugal force produced by Earth's rotation is larger than at polar latitudes. This counteracts the Earth's gravity to a small degree – up to a maximum of 0.3% at the Equator – and reduces the value of g at the equator.

So as we move from equator to pole value of g will increase. Hence option C is the correct option

• ## Question: What are the causes behind changing  in the colours of the soap or oil...

Posted in: AIPMT | Date: 04/10/2017

It is caused by thin film interference which depends on the thickness of the film. Option C is the correct option

• ## Question: Arteries and veins are named according to the organs that they are associated wi...

Posted in: NEST | Date: 04/10/2017

The pulmonary artery carries blood from the right ventricle of the heart to the lungs for oxygenation. Its name is derived from the Spanish word 'pulmon' meaning lungs

option A

• ## Question: Which of the following processes take(s) place in industrial production of baker...

Posted in: AIPMT | Date: 04/10/2017

Option D Molasses (a by-product of the refining of sugar beets and sugar cane) with very high sugar concentration is used in industrial production of baker's yeast because yeast needs sugar for growth. Molasses contains a mixture of sucrose, fructose, and glucose, (different forms of sugar) which are readily fermentable and the yeast hydrolyzes molasses to fermentable sugar which is required for its growth.

• ## Question: A shell explodes into three fragments of equal masses. Two fragments fly off at ...

Posted in: CET | Date: 04/10/2017

solution

• ## Question: A particle of charge q and mass m moves in a circular orbit of radius r with an ...

Posted in: AMITE | Date: 05/10/2017

Option C is the correct answer

• ## Question: The average age of a class of 22 students is 21 years. The average increased by ...

Posted in: Bank PO | Date: 05/10/2017

Total age of all students =22×21 Let the age of the teacher be t years Total age of all students + Age of the teacher =21×22 + t   ؞ The new average with teacher is (21×22 + t)/23

and the problem states that the new average with the teacher is increased by 1 i.e new average = 21+1=22

(21×22 + t)/23 = 22 or t= 44

Age of the teacher is 44 years

• ## Question: Two coherent sources of intensity ratio 100:1 interfere. Deduce the ratio of the...

Posted in: Physics | Date: 05/10/2017

Let the intensities of the light sources be I1 and I2 and  amplitude be a1 and a2

The intensity of a wave is proportional to the square of its amplitude​ i.e. I =a^2

؞​ I1/I2 = (a1/a2)^2 = 100/1 (given)  a12=100 or a1=10    (a2)^2= 1 or a^2=1

Imax/Imin= (a+1)2/(a-1)2= (10+1)2/(10-1)2= 11^2/9^2=121/81

Ratio of Imax:Imin= 121:81

• ## Question: A shepherd has 1 million sheep at the beginning of Year 2000. The numbers grow b...

Posted in: Bank PO | Date: 05/10/2017

The question seems to be wrong as the question states "number grow by x during the year" where it should be number grow by x% during the year

Let us assume the value of x to be 10%. Therefore, the number of sheep in the herd at the beginning of year 2001 (end of 2000) will be 1 million + 10% of 1 million = 1.1 million In 2001, the numbers decrease by y% and at the end of the year the number sheep in the herd = 1 million. i.e., 0.1 million sheep have died in 2001. In terms of the percentage of the number of sheep alive at the beginning of 2001, it will be (0.1/1.1)*100 % = 9.09%. Hence  x > y.  option A will be the correct answer

However, if we take increase was by x number (as mentioned in the problem) and decrease by y number then

The number of sheep in the herd at the beginning of the year 2001 (end of 2000) will be 1 million + x = (1,000,000+x)

In 2001, the numbers decrease by y and at the end of the year the number sheep in the herd = 1 million. then y number of sheep died

In that case 1,000,000+x-y =1,000,000 or x=y

Then option B will be the correct answer

• ## Question: Which of the following drug is used as a hypnotic drug? Please explain me the an...

Posted in: AIPMT | Date: 05/10/2017

Correct answer is B Luminal. Chemical name for Luminal is  Phenobarbitol; Phenylethylbarbiturate; Phenobarbituric acid . Phenobarbital is a barbituric acid derivative that acts as a nonselective central nervous system depressant and falls under the group of hypnotic.

Phenacetin is a pain relieving and fever relieving drug and it falls under the group called NSAID (Non-steroidal anti-inflammatory drug)

Quinine belongs to a class of drugs known as antimalarials. It is used for the treatment of malaria.

Penicillin is a group of antibiotics used for treating infections caused by susceptible gram-positive bacteria like Streptococci, Staphylococci, Clostridium, and Listeria genera

• ## Question: 35.4 mL of HCl is required for the neutr...

Posted in: AIPMT | Date: 05/10/2017

Volume of HCl V1=35.4 ml   Normality of HCl =N1

Molar mass of NaOH = 40 gm Normality of NaOH is N2= 0.275/40 N. Let the volume of NaOH be V2= 1000 ml

N1V1=N2V2 or N1X 35.4 = 0.275 X 1000/40 or N1= (0.275 X100)/(35.4X40) =0.194 N

Option C-  0.194 N is the correct answer

• ## Question: A person starting with 64 rupees and making 6 bets, wins three times and loses t...

Posted in: AMIE | Date: 05/10/2017

If each wager is for half the money remaining, each win lead to multiplying the amount by 1.5 times and each loss multiplying the amount by 0.5 times.

the person won three times and lost three times. So we need to multiply the initial amount by 1.5 thrice and the loss by 0.5 times thrice in any order.

So the final amount will be Rs. 64(1.5)(1.5)(1.5)(0.5)(0.5)(0.5) = Rs 27 (ina ll caes)

The loss will be 64-27 =37

option B will be the correct option

• ## Question: Mass of the earth is 81 times the mass of the moon and the distance between the ...

Posted in: Physics | Date: 06/10/2017

Mass of moon = M, Mass of earth =81M  Distance between earth and moon be d =60R, R=radius of earth

Let y be the distance from the moon where the gravitational force will be zero

At y, the gravitational pull by earth will be equal to that of moon

GM/y^2= 81GM/(d-y)^2 or 81y^2= (d-y)^2 or d-y=9y or d=10y.

So 60R=10y or y=6R

Option C is the correct option

• ## Question: Two points (4, p) and (0, q) lie on a straight line having a slope of 3/4. How s...

Posted in: Physics | Date: 06/10/2017

(4,p)X______________________Y (0,q)  Slope,3/4 = (p-q)/(4-0) or p-q=3

Option C is the correct answer

• ## Question: Which of the following dissolves in water but does not give any oxyacid solution...

Posted in: Chemistry | Date: 06/10/2017

OF2 dissolves in water but does not give any oxyacid solution. OF2 + H2O → 2HF + O2

Option B is the correct answer

• ## Question: At temperature 327$$^0$$C and concentration C, osmotic pressure of a solution is...

Posted in: AMIE | Date: 06/10/2017

P1V1/T1=P2V2/T2  P1=P, p2= 2 atms V2=2V1 since the concentration was halved.

T1=327+273=600  and T2= 427+273=700  P1V1/600=2(2V1)/700 or p1= 6X4/7=24/7

Option B is the correct answer

• ## Question: Which of the following will have the highest coagulating power for a ferric hydr...

Posted in: Chemistry | Date: 06/10/2017

Ferric hydroxide Fe(oH)3 is a positively charged solution. To coagulate we need a negatively charged solution.

By Herdy-Schulz rule -Coagulating power of an electrolyte is directly proportional to the valency of the active ions (ions causing coagulation).

Similarly, to coagulate a positive solution, such as Fe(oH)3 the coagulating power of different anions has been found to decrease in the order : [Fe(CN)6]4- > [CrO4] 2- > Cl-

Option D is the correct answer

• ## Question: If a solution of solute X contains 40% of X by weight of solution. 800 g of...

Posted in: Mathematics | Date: 06/10/2017

800 gm of solution X contains 40% solute. ie it contains 40/100*800=320 gm of solute X

After colling 100 gm of solute is precipitated. Therefore 220 gms of solute X in the solution

Percentage of the solute X in remaining solution is 220/700*100 = 31.4%

Option A is the correct answer

• ## Question: A first order reaction is 50% completed in 20 minutes at 27$$^{0}$$C, and in 5 m...

Posted in: AMIE | Date: 07/10/2017

Option B is the correct answer

• ## Question: The enthalpy of formation of H2$$_{o}$$ (l) is - 285.77 kJ mol$$^{-1}$$. The ent...

Posted in: AICEE | Date: 07/10/2017

H2I+2BOH⇒2BI+2H2O=ΔH=−285.77kJ/mol

H+OH–⇒H2O;ΔH==−56.07kJ/mol

The heat of ionization or the energy of dissociation in this reaction is equal to (–285.77 + 56.07) kJ/mol =-229.7 KJ/mol

Option B

• ## Question: The bending moment at a section of a beam is given by wx$$^3$$/6 then the expres...

Posted in: Physics | Date: 08/10/2017

option B is the correct answer

• ## Question: A body falls from a height h on a horizontal surface and rebounds. Then, it fall...

Posted in: AMITE | Date: 08/10/2017

Option B is the correct answer

• ## Question: Two vertical poles are of heights ‘X’ and ‘Y’, stand apa...

Posted in: Mathematics | Date: 10/10/2017

solution

• ## Question: If a bag contains 15 marbles out of which 5 are white, on adding ...

Posted in: AMIE | Date: 12/10/2017

Case 1 Probability of picking up a white marble = 5/15=1/3

Case-2  x white marbles were added.

Probability of selecting white marble = (5+x)/(15+x)=3/5 or 25+5x= 45+3x or x=10

Option D

• ## Question: If two dice are rolled at the same time, then please help me to find out th...

Posted in: AIEEE | Date: 12/10/2017

The number set of two dice adding to 10 or less than 10 are as follows

(1,1]) (1.2).......(1,6)

(2,1), (2.2)....(2,6)

(3,1), (3,2)....(3,6)

(4,1), (4,2)....(4,6)

(5,1) (5,2)....(5,5)

(6,1), (6,2)...(6,4)

P= 33/36=11/12

Option B

• ## Question: If a and f3 are the solutions, of the equation a tan θ + b sec θ = c...

Posted in: Mathematics | Date: 14/10/2017

The problem is misprinted. The problem should be  " if α and β are the solutions of the equation  a tan θ + b sec θ = c, then show that tan (α + β) =2ac/(a² - c²) "   and not 2ac/(2a² - c²)

Solution

a tan θ + b sec θ = c (given)

Rearranging the given equation we get, atan(θ) - c = -bsec(θ)   Squaring both sides, a²tan²θ - 2ac*tan(θ) + c² = b²sec²θ  Then Using the identity, sec²θ = 1 + tan²θ and simplifying the above, it reduces to:  (a² - b²)tan²θ - 2actan(θ) + (c² - b²) = 0   The above is a quadratic in tan(θ), which has two roots - tan(α) & tan(β)  So applying properties of quadratic equation,  Sum of roots: tan(α) + tan(β) = 2ac/(a² - b²) -------- (1)  and Product of roots: tan(α)*tan(β) = (c² - b²)/(a² - b²) -------- (2)  Therefore, tan(α + β) = {tan(α) + tan(β)}/{1 - tan(α)*tan(β)}  Substituting the values from (1) & (2) above,  tan(α + β) = [2ac/(a² - b²)]/[1 - (c² - b²)/(a² - b²)] = 2ac/(a² - c²)  Thus, tan(α + β) = 2ac/(a² - c²)

• ## Question: If the coefficients of three successive terms in the expansion of (1 + x)$$^n$$ ...

Posted in: Mathematics | Date: 14/10/2017

Let nC(r-1) = 45, nCr = 120 and nC(r+1) = 210

=> nCr / nC(r-1) = 120/45=8/3 and nC(r+1)/nCr = 210/120=7/4

nCr / nC(r-1)=[ ni /(r)i (n-r)i ]/[ni /(r-1)i (n-r+1)i] = (n-r+1)/r = 8/3 and (n-r)/(r+1) = 7/4

=> 4n -11r =7… eq-1  and 3n - 11r =- 3… eq-2

Subtracting 2nd eqn. from the 1st,

n = 10 and r = 3

• ## Question: A family of 4 members planned to go for a Journey to Goa by train during summer ...

Posted in: Mathematics | Date: 14/10/2017

To reach the path represented by the equation  6x - 7y+ 8=0 in the shortest possible time, the family has to travel through the path which is perpendicular to the path 6x - 7y + 8=0 and passes through the intersection of the paths whose equations are 2x - 3y - 4 =0 and 3 x + 4y -5 =0

To get the point of intersection of the two lines: 2x - 3y - 4 =0 and 3 x + 4y -5 =0, we need to solve the equation which will give the the point of intersection,O (x1,y1)

2x1 - 3y1 - 4 =0 ....line1

3x1 + 4y1 -5 =0......line 2

x1=31/17 and y1=(-2/17)

The slope of the given line(line-3) is  6x - 7 y + 8=0 , m1=6/7 The slope of the required line(shortest path) will be m2= -7/6 ,ince the shortest path will be perpendicular to line 3 and product of slopes of perpendicular lines are -1

The equation of the required line is : (y - y1)/(x - x1)=- 7/6

⇒ [y-(-2/17)]/(x -31/7)= (-7/6)

⇒ (17y+2)/(17x-31)=(-7/6)

⇒ 119x +102y= 205

Hence the equation of the path they should follow is 119x +102y- 205=0

• ## Question: Two straight roads intersect at an angle 60$$^{0}$$. A bus on one road is 2 km a...

Posted in: AIEEE | Date: 14/10/2017

Option D is the correct answer

• ## Question: One end of a diameter of a circle is (- 2, - 3) and centre is (2, -5). How can I...

Posted in: Bank PO | Date: 14/10/2017

Let the one end of the diameter be (x,y). The center (2,-5) is the midpoint of the diameter, whose other end is (-2,-3)

By using the midpoint formula

x+(-2)/2=2 and y+(-3)/2=-5 => x=6 and y = -7

Coordinates of the other end of the diameter is (6,-7)

• ## Question: The angle of elevation of the top of a tower from a point on the ground at some ...

Posted in: AMIE | Date: 14/10/2017

Option A is the correct answer

• ## Question: A person sitting in an aeroplane, which is flying at a certain height, observes ...

Posted in: AMITE | Date: 14/10/2017

solution

• ## Question: A point on the pole divides in a certain ratio. Both the parts subtend equal ang...

Posted in: Mathematics | Date: 14/10/2017

Solution

• ## Question: PQR is a triangular park such that PQ = PR = 20 m. A clock tower which is at the...

Posted in: AIEEE | Date: 15/10/2017

Option A is the correct answer

• ## Question: The angle of elevation of an incomplete tower is found to be 45$$^{0}$$ fro...

Posted in: AMIE | Date: 15/10/2017

Option B is the correct answer

• ## Question: In a triangle ABC, AP and CQ are the perpendiculars from the vertices A and C re...

Posted in: Mathematics | Date: 15/10/2017

Option B is the correct answer

• ## Question: In a right angled triangle ABC, right angled at B, the angle bisector of angle A...

Posted in: AIEEE | Date: 15/10/2017

Option D is the correct answer

• ## Question: In the given figure, PQ is diameter of a circle with centre O.  $$\angle PR... Posted in: AMITE | Date: 15/10/2017 ### Answer: Solution • ## Question: In a triangle ABC, PQ is parallel to BC such that, AP : PB = 1 : n. Then please ... Posted in: Mathematics | Date: 15/10/2017 ### Answer: Solution • ## Question: In the given figure, O is the centre of the circle and \(\angle$$POQ = 150...

Posted in: AIEEE | Date: 15/10/2017

Option C is the correct answer

• ## Question: A rocket fired vertically moves according to the relation s = at + b, where s is...

Posted in: AIEEE | Date: 16/10/2017

Solution

• ## Question: ABC is a vertical tower of height H. The angle of elevation of B from a point P,...

Posted in: AMIE | Date: 16/10/2017

Let AB= x and AC=y

Tan30 = x/2a => 1/√3= x/2a => x=2a/√3

Tan60=y/a => √3 =y/a => y= a√3

AB/BC = x/(y-x)  => (2a/√3)/(√3a-2a/√3) = 2:1

Option D is the correct answer

• ## Question: The length of the shadow of a vertical pole on level ground increases by 25 metr...

Posted in: AIEEE | Date: 16/10/2017

Let h be the height of the tower and x be the length of the shadow when the sun is at 60°

tan60 = h/x => x= h/√3  and tan 30= h/(x+25)  => 1/√3 = h/(x+25)  => 3h = h + 25√3 => 2h= 25√3

=> h = 25√3/2

• ## Question: If a field E is given, and E = 3y$$^{2}$$&nbs...

Posted in: AMIE | Date: 16/10/2017

Sorry the wrong solution got attached please see the correct solution

• ## Question: The sides of a right angled triangle ABC such that AB : BC: AC = 3 : 4 : 5. Ther...

Posted in: AIEEE | Date: 17/10/2017

Option C is the correct option

• ## Question: In figure, a common chord on two concentric circles of radii R and r meets t...

Posted in: AIEEE | Date: 18/10/2017

x2 + y2 + z2   = 8R2 + 2r2

• ## Question: A wheel is moving at the rate of 140 revolutions per minute. If radius of the wh...

Posted in: Mathematics | Date: 18/10/2017

The wheel moves at 140 rev/min. In 1 hour it is 140 X 60 rev.

In I rev the wheel will travel 2πr cm = 2X 22/7X 35 cm = 2X 22/7X 35 X10-5 kms

In 1 hour it will travel    140 X 60 X2X 22/7X 35 X10-5 = 18,480 X 10-3 Kms = 18.48 Kms

Option B is the correct answer

• ## Question: The mid-point P of the line segment joining the points A(–10, 4) and B(&nd...

Posted in: Bank PO | Date: 20/10/2017

P will divide the line segment CD in 2:3 ratio and y=6

• ## Question: Three dice are rolled. The probability of getting the same number on the three d...

Posted in: Bank PO | Date: 21/10/2017

If all the three dices are rolled simultaneously, they can fall in 6^3 =216 ways. If the same number has to appear in all the three dices, then the possible combinations are as follows.

(1,1,1), (2,2,2), (3.3,3), (4,4,4), (5,5,5) and (6,6,6)= 6 combinations

Probability of getting the same number on three dices are 6/216=1/36

Hence option B is the correct answer

• ## Question: In a figure quadrilateral ABCD is drawn to circumscribe a circle such that its s...

Posted in: CET | Date: 21/10/2017

Tangents drawn from an external point to a circle are always equal.

The quadrilateral, ABCD is drawn to circumscribe a circle such that its sides AB, BC, CD and AD touch the circle at P, Q, R and S respectively. Therefore A,B,C and D are external points from which tangents AS=AP=5, BP=BQ, CQ=CR=3 and DR=DS are drawn

BC=7.  => BQ + CQ =BC=7  =>  BQ= 7-3=4 ∴ BP=4

AB=x, => AP +BP = x => 5+4 =x  => x=9

Option B is the correct answer

Posted in: AMITE | Date: 21/10/2017

When a circle is inscribed in a square, the diameter of the circle is equal to the side length of the square.

The diameter of the circle is 28cm.  Area of the circle is 22/7X14X14 sqcm= 22X28 sq. cm.

The area of the square is  28 X28 sq. cm

∴ The are inscribed between square and circle is 28X28-22X28= 28(28-22) =28X6= 168 sq. cm

Option D is the correct answer

• ## Question: In a mile race, Akshay can be given a start of 256 metres by Bhairav. If Bhairav...

Posted in: Bank PO | Date: 22/10/2017

Bhairav (B) has given 256 meters(m) lead to Akshyay(A)

B will cover 1600 m, A will cover 1600-256=1344m. Let the time taken be t to complete the race and speed of  B and A be Vb and Va

∴ 1344/Va=1600/Vb  => Va/Vb= 1600/1344= 21/25......(i)

Similarly, B Covers 1600m when C covers 1600-64= 1536 m

∴ 1536/Vc= 1600/Vb => Vb/Vc= 1600/1536= 25/24

∴ Va:Vb:Vc= 21:25:24 => Va:Vc=21:24

∴ Speed of A is Va=21x and speed of C Vc=24x

Time taken by C to complete one and a half mile race= (1600X1.5)=2400m be T

T= 2400/24x=100/x.  In the same time A will run 100/x*21x=2100 m

∴ The winner will be Chinmay C by a  lead of 2400-2100=300m= 300/1600 mile =3/16mile

Option B is the correct answer

• ## Question: How should I calculate the average number of visitors in a theme park from Febru...

Posted in: Bank PO | Date: 22/10/2017

The number of visitors in January was 960.

The average number of visitors January-July is 870

∴ Total number of visitors January-July is 870 X 7= 6,090.

∴ Total number of visitors February-July =6,090-960= 5,130

Actual number of visitors in August was 827

∴ Total number of visitors February -August =5,130+827= 5,957

∴ Average number of visitors February-August= 5,957/7=851

Hence Option B is the correct answer

• ## Question: A pipe P can fill a tank in 12 hours. Another pipe Q can fill the tank in 18 hou...

Posted in: Bank PO | Date: 22/10/2017

The question has missing data. It needs to specify "how long the pipe was opened every day?"

Assuming it is opened for 1 hour every day, then the solution will be as follows

In 1 hour P will fill up 1/12th of the tank and in 1 hour Q will fill up 1/18th of the tank.

In 2 days (1/12 + 1/18)= 5/36 parts of the tank will be filled.

The tank will be filled in 36/5*2= 72/5=14.4 days

Option D is the correct answer.

• ## Question: A can complete a task in 24 days and B can complete the same task in 30 days. Th...

Posted in: Bank PO | Date: 22/10/2017

Option B is the correct answer

• ## Question: The ratio of radius of Earth to that of another planet is  $$\frac{2}{3}$$&...

Posted in: AIEEE | Date: 22/10/2017

Option B

• ## Question: Acceleration due to gravity is 'g' on the surface of Earth. What is the ...

Posted in: AIEEE | Date: 22/10/2017

We know that acceleration due to gravity, g on the surface of the Earth: g = GM/r2

Where M is the mass of the Earth, r the radius of the Earth (or distance between the center of the Earth and point on the surface of the earth), and G is the gravitational constant.   i.e.      g ∝ 1/r2

The acceleration due to gravity at a height above the surface of the earth is g'

g/g' = (r+h)2/r2  =>  ​g' = gr2/(r+h)2    =>​   ​g' =  g(6400)2/6432)2  = 0.99g

Option A is the correct answer

• ## Question: In an exhibition, 60% of the collections are from sales of cold drinks, rest is ...

Posted in: Bank PO | Date: 22/10/2017

The problem needs to be corrected as "If the number of water bottles sold is 1/3rd of the number of cold drinks sold, Help me to find the total number of cold drinks sold".

Solution

Let the number of cold drinks sold be '3x', then the number of water bottles sold will be 1/3*3x=x

Let the price of each bottle of cold drink be 'c' and each water bottle be 'w'

Total collection from the sales of cold drinks and water botlle= (3cx+wx)

60% of the collection is from cold drinks(given)

∴ 60/100*(3cx+wx) = 3cx  => 10cx= 6cx+2wx  => 4cx = 2wx  => w = 2c

Had 30 more cold drinks being sold, its contribution would have been 80%

∴ (3x+30)c = 80/100[(3x+30)c + wx] => 15cx + 150c = 12cx + 120c + 4wx

=> 15cx + 150c = 12cx + 120c + 4(2c)x  =>  5cx = 30c => x = 6

∴ Number of cold drinks sold, 3x = 3(6) =18

Option C is the correct answer

• ## Question: Two bodies are thrown upwards at the angles of 45$$^{0}$$ and 60$$^{0}$$&nb...

Posted in: AIPMT | Date: 22/10/2017

Let the body be projected at an angle θ to the horizontal with a velocity 'u'. The vertical height attained by the body is given by H= u2(Sinθ)2/2g   Now it is given that H1=H2

∴ (u1)2(Sinθ1)2/2g = (u2)2(Sinθ2)2/2g  => u1/u2 = Sinθ2/Sinθ1  =>   u1/u2 = sin60/sin45 = (√3 /2)/(1/√2)

=> u1/u2 = (√3/√2)   =√(3/2)

Ratio of their velocities will be √3:√2

The given options are misprinted and hence none of the optionis correct

Posted in: AIEEE | Date: 22/10/2017

Let the radius of each semi-circle be 'r'. Then the side of the square will be 2r

From the given figure we can calculate, 4+r+2r+r+2=18

=>​ 4r = 12 =>​ r =3

∴ ​Area of shaded semi-circles will be 4*πr2/2 = 2πr2= 2*(3.14)*9= 56.57 sq. cm

and area of the square is 18*18 =324 sq.cm

∴ Area of the unshaded region is (324-56.57) = 267.43 sq.cm

Hence Option D is the correct answer

• ## Question: In the following graph diagram, if slope is equal to -2.0x10$$^{-6}$$ ...

Posted in: Chemistry | Date: 23/10/2017

Solution

• ## Question: A metallic cylinder with 70 cm height and base diameter 15 cm is surmounted by a...

Posted in: AIEEE | Date: 23/10/2017

Option B is the correct answer

• ## Question: A cylindrical boiler, 5 m high, is 6 m in diameter. It has a conical lid. I...

Posted in: AMIE | Date: 23/10/2017

Cylinder

Diameter= 6m Radius r = 3m Height h1= 5m. Volume of cylinder V1= πr2h1  = (22/7)*3*3*5 m3 = 141.43m3

Conical lid

Diameter= 6m Radius r = 3m Height h2= 2m. Volume of cone V2= 1/3πr2h2= (1/3)*(22/7)*3*3*2= 18.86 m3

Volume of the solid = Volume of Cylinder(V1)+ Volume of conical lid (V2)= 141.43 + 18.86 = 160.29 m3

hence Option D is the correct answer

• ## Question: The total surface area of a cylinder of height 8 cm is 528 cm$$^{2}$$. It is mel...

Posted in: AMITE | Date: 23/10/2017

The height of the cylinder h=8 cm. Total surface area=528 cm2  Let r be the radius of the cyclinder

Total surface area of the cylinder is (2 π * r2 + 2 π * r * h) = 2 π r(r+h)

2 π r(r+h) =528 (given)   =>  2*(22/7)*r(r+8) = 528  =>  r2 +8r = 84  =>   r2 +8r - 84 =  0 => (r+ 14)(r-6) = 0

=>  r = 6 OR r = -14 (discarded as radius can't be negative)

؞  Volume of the cylinder V= π * r2*h

The cylinder is melted and recasted into 'n' number of spheres of radius r2=2 cm

Volume of n spheres = 4/3*π * r3*n .  Euating the volume of cylinder and spheres we get

π *6*6*8 =  4/3 *π*2*2*2*n   =>   n = 27

27 spheres can be obtained

Hence option D is the correct option

• ## Question: A hollow cylinder of internal and external radii 10 cm and 8 cm respectively and...

Posted in: AMIE | Date: 23/10/2017

Volume of hollow cylinder V = π(R2-r2)h where R= radius of the outer surface and r= radius of the inner surface

Volume of each cone v= 1/3π*(r1)2 *h2 where r2 = radius of the cone and h2=height of the cone

Let the cylinder be melted into 'n' number of cones. Then by equating the volume of hollow cylinder and cone we get,

π(R2-r2)h = n* 4/3π*(r1)3  =>  n = (100-64)X5X3/(3*3*5)   =>  n = 12

Option B is the correct answer

• ## Question: Volume of a cone with radius and height in the ratio 3 : 4 is 301.44 cm$$^{3}$$....

Posted in: Mathematics | Date: 24/10/2017

The ratio of the radius and height of the cone is 3:4. Let the radius be 3x and height be 4x

Volume of the cone V = 1/3πr2h  =>  1/3(3.14)(3x)2(4x)= 301.44  =>  1/3*3.14*9*4x3 = 301.44

=> x3 = 8  =>  x=2

Curved suraface area of the cone =πrl (l= slatn height) , l = √(r2+h2) = √(9x2+16x2)= 5x

πrl= 3.14*3x*5x= 3.14*15*4 = 188.4 cm2

Option D is the correct answer

• ## Question: Two trains, one travelling at 15 ms$$^{-1}$$ and the other at 20 ms$$^{-1}\... Posted in: AIPMT | Date: 24/10/2017 ### Answer: First Train: Speed u1= 15 m/s. Retardation a1= (-1) m/s Final velocity =0; Distance travelled before stopping be s1 SecondTrain: Speed u2= 20 m/s. Retardation a1= (-1) m/s Final velocity =0; Distance travelled before stopping be s2 0 -(u1)^2 = 2 (-1) s1 => -(15)^2 = -2s1 => s1 = 225/2 = 112.5 m 0 -(u2)^2 = 2 (-1) s2 => -(20)^2 = -2s2 => s2 = 400/2 = 200 m The distance between them after they stop = [500-(112.5+200)] = 187.5 m Option C is the correct answer => • ## Question: The height y and the distance x along the horizontal plane of a projectile on a ... Posted in: Physics | Date: 24/10/2017 ### Answer: Velocity is the change in the position of a body with time The height y (vertical distance) along the y-axis is given by y = (8t – 5t2) So we can get the vertical velocity by differentiating it over time. i.e. dy/dt =d/dt(8t-5t2) = 8-10t. At t=0, Vy=dy/dt = 8-10(0) = 8 The horizontal distance 'x' is given by x=6t ؞ Horizontal velocity Vx = dx/dt = d/dt(6t) = 6 The velocity (vector) with which the projectile is projected is 8i + 6j = √ 8^2+6^2 = √ 100 = +/- 10. Since velocity cannot be negative Option C -10m/s is the correct answer • ## Question: A boy jumps to a height of 2 m on the surface of Earth. Suppose the same bo... Posted in: AMIE | Date: 25/10/2017 ### Answer: Option C is the correct answer • ## Question: A particle moves in the xy plane with only an x-component of acceleration of 2 m... Posted in: Physics | Date: 25/10/2017 ### Answer: For the X- direction, Final velocity Vx, Initial velocity Ux,= 8 m/s, Acceleration a= 2 m/s2 Vx =Ux + at => Vx = 8 + 2t . therefore, velocity vector in x-direction Vx = (8 + 2t)i........(i) For the Y- direction, Final velocity Vy, Initial velocity Uy,= -15 m/s, Acceleration a= 0 Vy =-15 + (o)t => Vy = -15 therefore, velocity vector in x-direction Vy = -15j ....(ii) The total velocity vector at time t will be V = Vx +Vy = (8 + 2t)i. + (-15)j.) = √​ ((8 + 2t)2 + (-15)2) and at t=0 it will be √​ (64 + 225) = √​289 = 17 m/s • ## Question: A shell is fired from a cannon with a speed of 100 ms\(^{-1}$$ at an angle ...

Posted in: Physics | Date: 27/10/2017

Option A is the correct answer

• ## Question: An aluminium rod and a copper rod have the same length and resistance. The speci...

Posted in: AIEEE | Date: 27/10/2017

Resistance of a wire is given by R=ρ.L/A, where ρ  is the specific resistance of the wire,

A is area of cross-section of the wire, and L  is length of the wire and If V is volume of the wire

Volume V = A*L  => A = V / L,  Then ρ = A R / L = V R / L²

Hence R=ρ. L² /V …….(i)

If d is density and m is the mass of the wire, then   R=ρ. L²d /m

Let mass of aluminum be mA and that of copper be mc

∴ Ratio of mass of aluminum: mass of copper = mA /mc   = (ρA.LA²dA)/ (ρc.Lc²dc)

But LA= Lc   , ρA=2 ρC ,  and dc = 3dA

∴ mA /mc = (2/1)* (1/3) = 2/3

Hence option B is the correct answer

• ## Question: A point on a curve is said to be an extremum if it is a local minimum or a local...

Posted in: AMIE | Date: 27/10/2017

Let the curve be represented by the function, y = f(x)=3x4 −16x3 +24x2 +37

Differentiating the function we get

dy/dx =  12x3 −48x2+48x  For maxima and minima dy/dx = 0 ⟹12x3 −48x2+48x =0  ⟹12x(x2−4x+4)=0  ⟹   x(x−2)2=0

⟹x=0, 2  The second derivative d2y/dx2   will give the critical points  d2y/dx2  =36x2−96x+48  at x=0, d2y/dx2  =48    since d2y/dx2 =48>0 it means that  x=0 is local minima.  but at x=2, d2y/dx2 =0    so we can't apply second derivative test.

, we can only apply first derivative test.

⟹ dy/dx is negative for  all x < 0 and positive for all x > 0

Therefore  y=f(x)  has only one minimum (extremum) at x=0

Hence option B is the correct answer

• ## Question: A shell at rest, at the origin explodes into three fragments of masses 1 kg, 2 k...

Posted in: Physics | Date: 27/10/2017

OptionB

• ## Question: In the given figure, a cylindrical tank of cross sectional area A m$$^{2}$$...

Posted in: AMITE | Date: 29/10/2017

solution

• ## Question: At a telephone enquiry system, the number of phone calls regarding relevant enqu...

Posted in: AIPMT | Date: 29/10/2017

Option C is the correct answer

• ## Question: In the diagram, a string of length 'l' fixed at one end carries a m...

Posted in: Physics | Date: 29/10/2017

Option A is the correct answer

• ## Question: If same amount of electric current is passed through solutions AgNO$$_{3}$$ ...

Posted in: Chemistry | Date: 29/10/2017

According to Faraday's law of electrolysis, as the current passed will be same,

Weight of silver deposited/equivalent weight of silver =  Weight of Hydrogen liberated/equivalent weight of hydrogen

=>  1.08/108 = Weight of Hydrogen liberated / 1  => Weight of Hydrogen liberated = 0.01 gm

Now, 2 gms of hydrogen occupies 22,400 mL at STP

Therefore, 0.01 gm of hydrogen will occupy  (22,400 X 0.01) /2  = 112 mL at STP

Option B is the correct answer

• ## Question: Two substances A and B are present such that [A0] = 4[B0] and half-life of A is ...

Posted in: AMIE | Date: 29/10/2017

Initial concentration of A was [A]0 = 4[b]0, 4 times the initial concentration of B; Half-life of A is  5 minutes.

A's concentration will decrease as follows 4[b]0 => 2[b]0=>  [b]0  => 0.5[b]0 after each half-life

B's concentration will decrease as follows [b]0 => 0.5[b]0 Half-life of B is 15 minutes.

Hence after  one-half life of B = 3 half-lives of A = 15 munites concentration of A and B will be equal.

Option A is the correct answer

• ## Question: A liquid flows through a pipe of varying diameter. The velocity of the liquid is...

Posted in: AIPMT | Date: 30/10/2017

The velocity of an incompressible liquid is inversely proportional to the area of the circular pipe.

A1V1 = A2V2  where A is the area of the cross-section of the pipe and is the velocity of the liquid.

V2 = (A1V1)/A2 = [π(3)^2/π(1.5)^2] X 2 = 8 m/s

Hence option C is the correct answer

• ## Question: A photograph of a bacteria enlarged 50,000 times attains a length of 5 cm. What ...

Posted in: Mathematics | Date: 30/10/2017

(i) Actual length of the bacteria is 5/50,000= 0.0001 cms

(ii) Length after 20,000 enlargement will be 2 cms

• ## Question: In the given figure, assume that h is the height and r is th...

Posted in: AIEEE | Date: 31/10/2017

Option D is the correct answer

• ## Question: The sides AB, BC and CA of  $$\triangle ABC$$ ...

Posted in: AIPMT | Date: 31/10/2017

There are total 3+4+5 =12 points. To form a Δ we need to choose 3 points, except the ones which are collinear.

Side AB has 3, side BC has 4 and side AC has 5 collinear points.

hence the number of Δ s formed are 12C3- 3C3-4C3-5C3 = 220 -1 -4 -10 = 205

Option D is the correct answer

• ## Question: The number of candidates qualified from Institute C in 2008 and 2009 together is...

Posted in: Bank PO | Date: 31/10/2017

Insufficient data. Cannot be solved

• ## Question: Assume that an object of mass 40 kg having velocity 4 m/s collides with another ...

Posted in: Physics | Date: 31/10/2017

Body-1  =>  mass= m1=40 kg, velocity u1= 4 m/s

Body-2 =>  mass= m2=60 kg, velocity u2= 2 m/s

For perfectly inelastic collision, Loss in kinetic energy = (1/2)m1m2/(m1+m2)(u1-u2)^2 = 0.5 40*60(40+60)*(4-2)^2

= 48J

hence, option B is the correct answer

• ## Question: (11.92) $$^2$$ + (16.01) $$^2$$ = ? $$^2$$ × (3.85) $$^2$$

Posted in: Bank PO | Date: 31/10/2017

Use approximation to convert the decimals to nearest whole numbers

(11.92)^2 + (16.01)^2 = ?^2 × (3.85)^2   ͌     (12)^2 + (16)^2 = ?^2 × (4)^2   ͌    144 + 256/16= 25 = 5^2

? = 5

Option D is the correct answer

• ## Question: A TV tower has a height of 700 m. If the radius of the Earth is 6.4 x 10$$^... Posted in: AIEEE | Date: 31/10/2017 ### Answer: option A • ## Question: Two sources produce electromagnetic waves. Source B produces a wavelength that i... Posted in: AMIE | Date: 31/10/2017 ### Answer: The equation for photon energy is E = hc/λ i.e E α 1/λ => Eaλa = Ebλb => Eb = 2.1 X 10-18 *λ/3λ = 0.7 X 10-18 = 7.0 X 10-19 J option B is the correct answer • ## Question: A VCR and TV were bought for Rs 8,000 each. The shopkeeper made a loss of 4% on ... Posted in: Mathematics | Date: 01/11/2017 ### Answer: C.P of VCR = C.P of TV = 8,000. 4% loss on VCR. S.P. of VCR =96% of Rs. 8,000 = Rs. 7,680. 8% gain on TV. S.P. of TV =108% of Rs. 8,000 = Rs. 8640. Total S.P. = 16,320 Total C.P. 8,000 + 8,000 = 16,000 Profit/Loss % = (S.P. - C.P.)/C.P/ X 100 = 2% The shopkeeper made 2% profit on entire transaction • ## Question: The cost of an article was Rs 15,500. Rs 450 were spent on its repairs. If it is... Posted in: Mathematics | Date: 01/11/2017 ### Answer: C.P = 15,500. Repairs =Rs 450. Total cost = Rs. (15,500 + 450) = Rs. 15,950. Sold for 15% profit S.P = 1.15 X 15,950 = 18,342.5 Selling price of the article = Rs.18,342.50 • ## Question: In the figure given below, a 10 g bullet moving directly upwards at 1000 m/s str... Posted in: Physics | Date: 01/11/2017 ### Answer: mass of bullet= m1 = 10gms = 0.01 kg. initial velocity of bullet = u1= 1000m/s. final velocity of bullet v1=400m/s mass of block= m2 = 5 kg. initial velocity of block = 0. final velocity of block v2 By applying conservation of momentum, we get m1u1= m1v1 + m2v2 => v2 = m1/m2*(u1-v1)= (0.01/5)X 600. The height traveled by the block h = V2^2/2g ( g=9.8 m/s2) = (0.01X 600/5)^2/(2X9.8) = 0.073 m Option B is the correct answer • ## Question: A man fires a bullet standing between two cliffs. First echo is heard after 3 s ... Posted in: AICEE | Date: 01/11/2017 ### Answer: Option C is the correct answer • ## Question: How to divide Rs.5500 between A and B so that A’s share at the end of 3 ye... Posted in: Bank PO | Date: 01/11/2017 ### Answer: Let A's share at present be a and B's share at present be b The problem states that a(1+20/100)^3 = b(1+20/100)^5 => a/b = (120/100)^5-3 => a/b = (6/5)^2 => a/b = 36/25 ؞ a= 36/(36+25)*5500 = 36/61*5500= 3246. b= 25/(36+25)*5500= 2254. hence A's present share should be Rs 3246 and B's share Rs 2254. None of the options is correct. Also, note that if A's share in 3 years has to be equal to B's share in 5 years with the same rate of interest, then A's present share has to be greater than B's present share. In all the options except option number A, B's present share is given as more than that of A's present share and hence cannot be correct • ## Question: The speed of a boat is 5 km/h in still water. If it crosses a river of width 1 k... Posted in: AMIE | Date: 01/11/2017 ### Answer: Option C i.e. velocity of river's water= 3km/hr is the correct answer • ## Question: The value of is (1+\(\sqrt{3}i)^5 + (1 - \sqrt{3}i)^5$$

Posted in: BITSAT | Date: 01/11/2017

Let |z1| = |1 + √3i|^5   and |z2| = |1 - √3i|^5.  (1 + √3i)^5 + 1 - √3i)^5 = (√​(1 + 3)^5 + √​(1 + 3)^5 ​= 2^5 + 2^5 = 64

Hence option D is the correct answer

• ## Question: A boatman can row with a speed of 10 kmh$$^{-1}$$. If a river of width 2 km flow...

Posted in: AIPMT | Date: 01/11/2017

solution

• ## Question: How many digits will be there to the right of the decimal point in the product o...

Posted in: Bank PO | Date: 01/11/2017

When we multiply decimals, the decimal point is placed in the product so that the number of decimal places in the product is the sum of the decimal places in the factors.

Let’s compare two multiplication problems that look similar:  2.04 X 1.94 and 2.04 and 1.95

2.04 X 1.94 = 3.9576  Add 2 decimals of 2.04 and 2 decimals of 1.94 = 4 decimal places.

however, if the last digit of the product of the last two digit is 0, then we need to reduce one decimal place as in case of  2.04  X 1.95  = 3.9780 but the answer can omit the final 0 after decimal places.

hence in the above problem without actually multiplying we can  say that number of decimal place will be 5+3 =8 but the product of last digits 8 and 5 being 40, ending with 0, we can omit the 0 and reduce the number of decimal places by 1

Hence it will be 8-1=7 option C

• ## Question: A disc of radius r = 20 cm is rotating about its axis with an angular speed of 2...

Posted in: AMIE | Date: 01/11/2017

Radius of disc 'r' =20 cm and angular velocity ω = 20 rad/s

Then linear velocity of point A which is on the rim, v = rω = 20*20 = 400 cms/s = 4 m/s

option D

• ## Question: A hospital uses an ultrasonic scanner of frequency 3.2 MHz to locate tumours in ...

Posted in: BITSAT | Date: 02/11/2017

The velocity of the ultrasound wave, v, is the product of its wavelength, λ , and its frequency, f.

Wavelength of a wave = velocity of the wave / frequency of the wave

λ = v/f,             v = 1.6  km/s = 1.6 X 10^3 m/s, f = 3.2MHz = 3.2 X 10^6 Hz

λ = (1.6* 10^3)/f(3.2*10^6) = 0.5*10^-3 m = 0.5 mm

Option B is the correct answer

• ## Question: In the given figure, a particle starts from rest. Its acceleration at time ...

Posted in: AIPMT | Date: 02/11/2017

Slope of the graph is m= -5/6 m/s2 per sec. Intercept c = 5 m/s2.By using the eqn. y =mx + c , we can see that the acceleration varies with time as  a= -5/6t + 5 where 't' is the time.

a= dv/dt = -5/6t + 5    Integrating ⌠​​dv (from 0 to v) = ​ ⌠​(-5/6t +5) dt (from 0 to t), we get

=> v = -5/12t^2 +5t  From the graph, we can see that acceleration is decreasing with time and becomes 0 at t=6s. when  v will be vmax. Using t=6 we get vmax = -5/12(36) + 5(6) = -15 + 30 =15 m/s

Hence option B is the correct answer

• ## Question: An equilateral triangle of side a is inscribed in a circle as shown below. The...

Posted in: Mathematics | Date: 04/11/2017

The question cannot be answered because the location of point D is not specified. Only if AOD is a straight line with O as the center of the circle, then BD = DC = a/√3 Option E

• ## Question: In the following figure AB is a diameter, O the center of the circle and OE ...

Posted in: Mathematics | Date: 04/11/2017

Option E is the correct answer (Proof follows)

OE is perpendicular to AB ؞ <BOE = 90o. But EOC = 60o ؞<BOC =30o

In Δ AOE, AO=EO (both are radius) <AOE =90o  ​؞​ <OAE = <AEO = 45o

In Δ BOC, BO=CO (both are radius) <AOE =90o  ​​ <BOC = 30o ؞ <OCB = <OBC = 75o

Now in Δ ABD, <BAD=45o and <ABD=75o ؞ <ADB = 180-(45+75) = 60o

؞ <EDB + <BOC = 60o + 30o = 90o

• ## Question: Two circles of radii 10 cm and 15 cm intersect with each other such that the dis...

Posted in: Mathematics | Date: 04/11/2017

Option A is the correct answer

• ## Question: In a circle of radius 13 cm, there are two chords PQ = PR = 12 cm. Then the leng...

Posted in: Mathematics | Date: 04/11/2017

option C is the correct answer

• ## Question: What is the value of $$\frac{\cos A} {1-\sin A}- tan A$$?

Posted in: Mathematics | Date: 04/11/2017

Option D

• ## Question: What is the value of 2sin$$^2\theta$$  - $$sin^4\theta$$ +&n...

Posted in: Mathematics | Date: 04/11/2017

Option C

• ## Question: Two identical charges (Q each) are separated by a certain distance. A third char...

Posted in: Physics | Date: 04/11/2017

Q_____a________q______a________Q

Let the charge q be placed at the midpoint of the line joining Q and Q

For a system of charges to be in equilibrium, the net force on all the three charges must be zero. F=0 Hence the charge q must be negative so that forces due to the other two charges will act in opposite direction.

The force on one of the charge Q by the other charge Q is KQ^2/(2a)^2 and the force on the same charge due to q is KQq/a^2

F=KQ^2/4a^2+ KQq/a^2 = 0 ⇒ q = -Q/4 The magnitude of the force will be Q/4.   Hence option B is correct

• ## Question: In a circle of radius of a` an isosceles triangle ABC is inscribed as shown bel...

Posted in: Mathematics | Date: 04/11/2017

Option C is the correct answer

• ## Question: The radius of the circle in which an isosceles triangle of sides 20 cm, 20 cm an...

Posted in: Mathematics | Date: 05/11/2017

Option D

• ## Question: A boy aims a gun at a bird from a point, at a horizontal distance of 100 m. If t...

Posted in: AIPMT | Date: 05/11/2017

Time taken by the bullet to cover to cover 100 meter horizontally = d/v = 100/500 = 0.2 s.

In 0.2 secs, the bullet will fall vertically by the distance h =gt^2/2 = 10*0.04/2 =0.2 m = 20 cms

Option D is the correct answer

• ## Question: What is the value of (sec$$^\theta$$- cos$$^\theta$$) (cosec$$^\theta$$&nbs...

Posted in: Mathematics | Date: 05/11/2017

Option C

• ## Question: An electric current passes through a long straight wire. At a distance 5 cm from...

Posted in: AMIE | Date: 05/11/2017

The magnitude of the magnetic field (B)at distance R from the center of the wire produced by current (I) in a wire of infinite length is    B = µoI/2πR .where µo is the magnetic permeability constant, If all other conditions remain unchanged, the strength of the magnetic field B varies inversely as distance from the wire

؞B1R1=B2R2 ⇒  B2= B*5/20 =B/4

Hence, option B is the correct answer

• ## Question: Find the value of x if cos35° cosec55° + tan63° tan27...

Posted in: Mathematics | Date: 05/11/2017

Option D is the correct answer

• ## Question: In the question, two equations (I) and (II) are given. Help me to solve both the...

Posted in: Bank PO | Date: 05/11/2017

By solving  the equations (i) and (ii) we get x=9 and y=-2  since 9 > 0 >-2;  hence option A is the correct answer

• ## Question: If the density of a small planet is the same as that of Earth, while the radius ...

Posted in: AIPMT | Date: 06/11/2017

We know F= mg = GmM/R^2 ⇒ g = GM/R^2 (where M is the mass of the body and R = radius of the body

But M= ρV ( where ρ= density of the body and V=volume of the body= 4/3πR^3) ؞ g = 4/3πGρR^3/R^2

؞g α R*ρ  ⇒ ge/gp= Re*ρe/Rp*ρp ( ge and gp are respective gravitation on earth and planet, Re and Rp are their respective radii and  ρe and ρp are respective  densities) But ρe = ρp as densities are equal

ge/gp= Re/Rp ⇒ gp= ge*Rp/Re = g* 0.2R/R =0.2g

Hence option A is the correct answer

• ## Question: A train starts moving at the speed of 60 kmph with its speed increasing every 3 ...

Posted in: Bank PO | Date: 06/11/2017

Option B is the correct answer

• ## Question: In the question, two equations (I) and (II) are given. Help me to solve both the...

Posted in: Bank PO | Date: 06/11/2017

x^3-25 = 50X3-50=> x^3= 25+ 100 =125 => x= (125)^1/3 = 5

y^2 - 3√729= 5+(121/11) => y^2 = 9 + 16 =25 => y=5

؞ x=y Option E

• ## Question: Atul drew 1 card at random from a well shuffled pack of 52 cards. What is the pr...

Posted in: Bank PO | Date: 06/11/2017

Total number of cards =52

Total number of jacks of black color= 2 (jack of clubs and jack of spades)

P(getting a black of Jack) = 2/52=1/26

Hence option D is the correct answer

• ## Question: Help me to find the value of sin(90° – $$^\theta$$ ) . ...

Posted in: Mathematics | Date: 06/11/2017

sin(90-θ) = cosθ and cos(90-θ)=sinθ

LHS of the expression sin(90-θ).cos(90-θ) = cosθ.sinθ

RHS of the expression tanθ/sec^2θ= (cos^2θ*sinθ)/cosθ = cosθ.sinθ

؞ LHS = RHS option D is the correct answer

• ## Question: Which of the following values is the same as sin (80° – x)?

Posted in: Mathematics | Date: 06/11/2017

Let 80-x = θ  Therefore, sin(80-x) =  sinθ = cos(90-θ) = cos(90-(80-x))= cos(10+x)

option C is the correct answer

• ## Question: The sum of area of two circles touching internally is 500.5 sq cm. If the distan...

Posted in: Mathematics | Date: 06/11/2017

Let the radius of the bigger circle be R and smaller circle radius be r.

؞π(R^2+r^2)= 500.5= 1001/2 ..(i) and R-r=3.5=7/2..(ii)

=> 22/7(R^2+r^2)=1001/2=> (R^2+r^2)= 637/4 from (ii) R = r+7/2 => R^2 = r^2 + 7r + 49/4 putting it in (i) we get

r^2 + 7r + 49/4 +r^2 = 637/4 => 2r^2 + 7r+ 49/4 = 637/4 => 8r^2 +28r-588 =0 => 2r^2 -14r +21r-147=0 => r=7, -21/2

Since radius can't be negative, discard-21/2 ؞ r=7  R= 7 +7/2=21/2. R/r = (21/2)/7= 21/14=3/2

hence option B is the correct answer

• ## Question: In the following figure, BOA is a quadrant and a semicircle is drawn on the hypo...

Posted in: Mathematics | Date: 06/11/2017

Area of the quadrant = π r2/4 (r=10cm) = 25π cm2; Area of the semi-circle drawn on the hypotenuse of the

isosceles Δ = π R2/2(R= 5√2 cm) =25π cm2 (since hypotenuse of the issocles Δ of side 10 cm = 10√2)

Area of the issoceles Δ =1/2*10*10=50 cm2

؞ Area of unshaded region = area of semi-circle- (area of quadrant- area of isosceles Δ) = 25-25+50 = 50cm2

hence option D is the correct answer

• ## Question: In a square sheet of side 28 cm, four circular parts are cut as shown in the fig...

Posted in: Mathematics | Date: 06/11/2017

Area of the sheet = 28X28 = 784 cm2. Radius of each circle is 28/4= 7cm. Area of each square = π 7^2 = 49π=  154 cm2

Area of remaining sheet = 784 - 4(154)= 784-616= 168 cm2

Hence option B is the correct answer

• ## Question: In the following figure, the diameter AB = 13 cm and BC = 5 cm, then the area of...

Posted in: Mathematics | Date: 06/11/2017

Diameter AB of the circle =13 cm. Radius = 13/2 cms. Area of the circle = (13/2)^2π= 42.25π

Side AB = 13 and BC=5 Now ABC is a right angle Δ because the angle subtended by diameter on the circumference of the circle is a right angle. Therefore AC= √(169-25) = 12, Then area of the Δ ABC = 1/2*12*5 = 30 cm2.

؞ Area of the shaded region = (42.25π- 30)cm2. Hence option B is the correct answer

• ## Question: Help me to find the equation of a line with y-intercept as 3 and passing through...

Posted in: Mathematics | Date: 07/11/2017

Let the equation of the line be y = mx+c where m is the slope of the line and c is the y-intercept. Since the line passes through the point (13,-11) and y-intercept= 3(given), -11=m*13+3 => m=-14/13 Substituting the value of m in the line equation we get, y=-14x/13+3 => 14x+13y-39=0  will be the equation of the line.

None of the options is correct. The equation of the line should be 14x+13y-39=0

• ## Question: In the given figure, ABCO is a square with diagonal $$^{\sqrt2}$$ cm. ...

Posted in: Mathematics | Date: 07/11/2017

ABCO is a square. Therefore, diagonals AB=OB=√2 cm. OB is the radius of the circle. Therefore the circumference of the circle= 2π*√2= 2√2π cms. Hence option C is the correct answer

• ## Question: Circumference of a circle is equal to the perimeter of a square. If perimeter of...

Posted in: Mathematics | Date: 07/11/2017

The perimeter of the square = 44 cms. ؞ Each side of the square = 44/4 = 11 cms. ؞ Area of the square =11*11= 121 cm2

The circumference of the circle with radius r= 44.   2πr = 44 =>  πr =22  =>22r/7= 22   => r =7 Area of the circle= 49π= 49*22/7= 154 cm2

Difference between the area of circle and that of square = 154- 121=33 cm2. Hence Option A is the correct answer

• ## Question: In the figure given below, ABCD is a square with each side measuring 7 cm and a ...

Posted in: Mathematics | Date: 07/11/2017

Area of the square ABCD= 7*7= 49 cm2. Area of the circle with radius 7/2 (radius = half of the side of the square)

= 22/7*(7/2)(7/2) = 77/2 cm2. Area of the shaded region = 0.5*(area of square-area of circle) = 0.5 *(49-77/2)

= 0.5*(98-77)/2= 0.5*21/2 =5.25 cm2 Option A is the correct answer

• ## Question: Past records show that on an average, 1 house out of 1000 in a certain district ...

Posted in: Mathematics | Date: 07/11/2017

Option A

• ## Question: The escape velocity of a body on Earth’s surface is v$$_e$$. If a bod...

Posted in: Physics | Date: 07/11/2017

Ve = √(2GM/R)  where Ve = escape velocity at earth's surface, G universal gravitational constant, m= mass of earth and

R=radius of earth=distance between the center of masse of earth and the body. Now 3V> ve

As R→ ​R∞, 1/R∞ →​ 0 so    3V> ve →​ 0  Hence the speed at infinity will be 0

Option A is the correct answer

• ## Question: The given figure consists of four small semicircles and two big semicircles. If ...

Posted in: Mathematics | Date: 07/11/2017

Radius of bigger circles = R = 20 cms  and smaller circles = r =10 cms.(Diameter of smaller circle= radius of bigger circle)

Shaded region = 3 smaller semi-circles + 1 bigger semi-circle - 1 smaller semicircle

Perimeter of shaded region = 3π(10) + π(20) - π(10) = 40π = 125.71 cms

Area of the shaded region = 3π(100)/2 + π/2(400-100) = 150π + 150π =  300π = 942.85cm2

Hence option B is the correct amnswer

• ## Question: An equilateral triangle ABC is inscribed in a circle of radius R. Then the side ...

Posted in: Mathematics | Date: 07/11/2017

Option C is the correct answer

• ## Question: A train 100 metres long, moving at a speed of 50 km per hour, crosses another tr...

Posted in: Bank Clerical | Date: 08/11/2017

Lenght of train-A = 100 m and length of train-B= 120 m. Speed of train-A = 50 kmph and speed of train- B = x kmph

If train-A has to cross the train-B the distance traveled by A will be the sum of the length of the trains A and B= 100+120=220m = 0.22km Sice the trains are traveling in the opposite directions, the relative speed of train A will be the sum of the speed of A and B = (50 + x) kmph.  Since time = distance/speed , the time to cross the train- B is 6 secs= 1/3600 hr.

6/3600= 0.22/(50+x) =>​ 6(50 + x) = 22*3600/100= 50+x = 22*6 =>​ x = 132-50 => x=82 kmph

Option B is the correct answer

• ## Question: Two circles intersect at two points P and Q such that PQ = 24 cm. If the radii o...

Posted in: Mathematics | Date: 08/11/2017

Option D is the correct answer

• ## Question: Who among the following became the Chairman of Tata Sons following the retiremen...

Posted in: Bank Clerical | Date: 08/11/2017

option E- Cyprus Mistry

• ## Question: In a row of boys, Prakash is sixth from the right and Bimal is fifth from t...

Posted in: Bank PO | Date: 09/11/2017

1_2_3_4_5_6_7_8_9_10_11_12_13_14_15_16_17_18

Before, 5th fm right  →   B                                     P →  6th from left

After                                P                                     B

Bimal is fifth from left and Prakash 6th from right. When they interchange Bimal is thirteenth from left. i.e. 13th from right = 6th from left => there are 13+6-1 =18 positions. Hence after interchange, Prakash is 14th from the right.

Hence option B is the correct answer

• ## Question: Kuntal walks 10 kilometres towards north. From there, he walks 6 kilometres towa...

Posted in: Bank PO | Date: 09/11/2017

option B

• ## Question: A boat P travels 40 km upstream from point A to B in 10 hours and from point B t...

Posted in: Bank PO | Date: 09/11/2017

A ______30___________C____10_____B

Distance AC=30 Kms, AB=40 kms  Let speed of boat P be 'x' speed of boat Q be 'y' and speed of stream be 'z'

Relative speed of P upstream = x-y and speed of Q upstream z-y. Relative speed of P downstream = x+y and speed of Q upstream z+y.  Now P travels from A to B = 40 kms upstream in 10 hours and B to A downstream in 5 hours.

time =distance/speed Therfore, x-y= 40/10 =4..(i)  and x+y = 40/5=8 ...(ii) solving (i) and (ii) we get x= 6 and y=2

Speed of boat P = 6 kms/hr  and speed of stream = 2 kms/hr and Speed of boat Q = z-2= 30/5=6 => z= 8 kms/hr

Now, P starts from A and Q starts from C  and Pand Q will meet at D after t hours.

t = 30/(Speed of P upstream+speed of Q downstream)  = 30/(4+10) = 15/7

In 15/7 hours P will travel 15/7*4= 60/7 kms upstream from A., = 40-60/7 =220/7 kms from B.

Therefore P and Q will meet at 220/7=  31.4 kms form B

Hence option A is the correct answer

• ## Question: Village K is towards which direction of village N? I.  Village M is to t...

Posted in: Bank PO | Date: 09/11/2017

K ____M

D____ N

Either statement specifies the direction of K w.r.t N

Hence option C is the correct answer

• ## Question: A and B started moving simultaneously from P and are going towards Q; their spee...

Posted in: Bank PO | Date: 10/11/2017

Speed of A = 36 km/hr. Therefore, Distance traveled by A in 2 mins = 36/60*2= 12/10kms = 1200 meters

Speed of B = 15 m/s. Therefore, Distance traveled by B in 2 mins = 15*120= 1800 meters

Distanc ebetween them after 2 mins = 1800-1200 = 600 meters

Option C

• ## Question: An aeroplane has to take a flight from an airport which is 778.5 m away from the...

Posted in: AMIE | Date: 11/11/2017

Let the <ACB= θ. tanθ= 450/778.5 =0.5773  Therefore θ= tan-1(0.5773) =30o

Option B is the correct answer

• ## Question: Which of the following brands is the least expensive per ounce?

Posted in: GATE Exam | Date: 11/11/2017

Price of W =0.21/6= $0.035/oz; Price of X =0.48/16=$0.03/oz

Price of Y=0.56/20= $0.028/oz Price of Z0.56/20=$0.03/oz

Y is least expensive per ounce Option C

• ## Question: At present, Reena's age is eight times her daughter's age. Eight years f...

Posted in: Bank PO | Date: 11/11/2017

Let Reena's age be x years and her daughter's be y years.  x=8y

Eight years from now, (x+8)/(y+8)= 10/3 => 3x+24 =10y+80 => 24y+24= 10y+80  => y=4. Therefore, x = 8*4=32

Reena's present age is 32 years

Optiopn A is the correct answer

• ## Question: In the following question, two equations numbered I and II are given. Help me&nb...

Posted in: Bank PO | Date: 12/11/2017

15p^2 - 26p +8 = 0=> 15p^2 - 20p -6p +8=0 => 5p(3p-4)-2(3p-4) => p=2/5 OR p=4/3

. 15p^2-2q-1=0 , When p=2/5, q= 1/2[15(4/25)-1] = 7/10 Therefore p<q

When p=4/3, q= 1/2[15(16/9)-1] = 77/6 Therefore p<q

Option D is the correct answer

• ## Question: The average age of 8 persons in a committee is increased by 2 years when two men...

Posted in: Bank PO | Date: 12/11/2017

If average age is increased by 2 years, total age is increased by 16 years

Total age of the two women = (35+45)+16 = 96 years Average of the two women is 96/2 = 48 years

Option A

• ## Question: When a force F acts on a body of mass m, the acceleration produced in the body i...

Posted in: Physics | Date: 12/11/2017

Solution

• ## Question: A cyclist starts from the centre 'O' of a circular park of radius 1 km, ...

Posted in: Physics | Date: 12/11/2017

solution

• ## Question: From his house, a man walks towards north and covers 15.5 km. Then, he turns lef...

Posted in: Bank PO | Date: 12/11/2017

solution

• ## Question: If the LCM of the first 100 natural numbers is N, then find the LCM of the first...

Posted in: GATE Exam | Date: 12/11/2017

N is the LCM of first 100 natural numbers.

Now 101 is a prime number, so 101 and N do not have any common factors. Hence their LCM = 101XN

102= 2X51, since 2<100 and 51<100, 102 divides N

103 is a prime number, no common factors between 103 and N

104= 52X2; since 2<100 and 52<100, 105 divides N

105 = 21X5; since 5<100 and 21<100, 105 divides N

Hence, LCM of first 105 natural number is NX101X103

Option B is the correct answer

• ## Question: For the differential equation $$\frac{dy}{dt}+5y=0$$ with y(0) = 1, the gen...

Posted in: GATE Exam | Date: 12/11/2017

solution

• ## Question: A and B borrow a total sum of Rs. 30,000 at simple interest from C at 4% p.a. fo...

Posted in: Bank PO | Date: 12/11/2017

Let the sum borrowed by A be x and by B be y

Interest paid by A = IA= x*4*5/100 and Interest paid by B = IB= y*5*4/100

Since interest paid by A is double that of B's; IA=2(IB) =>​ x/5 = 2y/5 =>​ x = 2y

x + y =30,000 =>​ ​ 2y + y = 30,000  =>​ y = 10,000. Therefore, x = 20,000

Sum borrowed by A is Rs. 20,000.00

Option B

• ## Question: Excluding stoppages, the average speed of a bus is 45 kmph and including stoppag...

Posted in: Bank PO | Date: 12/11/2017

Due to stoppage the bus travels (45-36) = 9 kms less.

Time taken for traveling 9 kms = 9/45*60= 12 mins

hence the stoppage is 12 mins Option B

• ## Question: Kalicharan gets some coins made of an alloy of gold and silver. The alloy with a...

Posted in: Bank PO | Date: 12/11/2017

In 100 gms of alloy-1(A1) - Gold = 20 gms and Silver = 80 gms

In x gms of alloy-2 (A2) - Gold= 40/100*x = 0.4x and Silver = 60/100*x = 0.6x

After mixing, ratio of Gold: silver = (20+0.4x)/(80+0.6x)= 32/68  =>​ x= 150

150 grams of second alloy was mixed with 100 grams of first alloy

Option E is the correct answer

• ## Question: What approximate value will come in place of the question mark (?) in the follow...

Posted in: Bank PO | Date: 12/11/2017

approximate value of cube root to3√926.158 is 3√1000.     3√1000 = 10

approximate value of cube of (12.99)3 is 13^3 =  2197

approximate value of cube of 74.98% of 679.8 = 75% of 680 = 3/4*680 = 510

3√926.158 + (12.99)3 + 74.98% of 679.8 = 10+2197+510=  2717= (52.12)^2

?= 52.12 Option B

• ## Question: What will come in place of the question mark (?) in the following number series?...

Posted in: Bank PO | Date: 12/11/2017

Option B Missing number is 4576

numbers 4569   4571  4576 4586  4603  4629  4666

Difference        2         5      10       17       26      37

Difference             3          5          7        9        11

• ## Question: Three horses are tethered at the three corners of a triangular plot of sides 12 ...

Posted in: Mathematics | Date: 12/11/2017

solution

• ## Question: The period of the signal g(t) = 2cos(10t + 1) + sin(4t − 1) is equal to

Posted in: GATE Exam | Date: 13/11/2017

The period of the sine and cosine function is 2π because the sine wave repeats every 2π units.

The period of k*cos(ax+b) or k*sin(ax+b) is 2π/a

Therefore, the period of cos(10t+1) = 2π/10 = π/5 and period of sin(4t-1) = 2π/4= π/2

The fundamental period of  g(t) = 2cos(10t + 1) + sin(4t − 1) will be the LCM of the fundamental periods for each of the componenet term in x(t) i.e. LCM of π/5 and π/2 is π

Option B is the correct answer

• ## Question: What approximate value will come in place of the question mark (?) in the follow...

Posted in: Bank PO | Date: 13/11/2017

1249.69 ÷ (49.94) + 7(17/41) of 942.99 + 69.87% of 800 = 1250/50 + 304*943/41 + 70/100*800=25 + 6992 + 560 = 7577

Option C is the correct answer

• ## Question: Mona travelled 3 km southwards. Then, she turned right and travelled 5 km. Then ...

Posted in: Bank PO | Date: 13/11/2017

Mona traveled 3 kms south and then turned right and traveled 5 kms in the west direction and again turned right and traveled 7 kms in North direction

Now she is traveling in North direction. Hence option C is the correct answer

• ## Question: A solution contains a mixture of liquid A and B in the ratio of 3 : 2. When 10 l...

Posted in: Bank PO | Date: 13/11/2017

In the initial solution let the volume of A be 3x and that of B be 2x. When 10 litres of solution is taken out, 6 liters of A and 4 liters of B is taken out. Then 10 liters of B is added.

Therefore, (3x-6)/(2x-4+10)=1/2 => 3x-6 = x + 3 => 2x=9 => x= 9/2 => 5x = 45/2 = 22.5

Volume of initial solution = 22.5 liters Hence Option E is the correct answer

• ## Question: Mr. William and Mr. John deposited a total amount of $72,000 in a common account... Posted in: Bank PO | Date: 13/11/2017 ### Answer: William share: John's share = 7:9 Total amount deposited$ 72,000. William's share = $7/16*72,000=$31,500

John's share = $40,500. William withdrew$ 7,500 and John withdrew $x. (31,500-7,500)/(40,500- x) = 4/5 => 24,000/(40,500-x) = 4/5 => x = 40,500-30,000 =$10,500

Option C is the correct answer

• ## Question: If the error in the measurement of the momentum of a particle is (+100%). Then t...

Posted in: AIEEE | Date: 13/11/2017

Option D is the correct answer

• ## Question: Which one is a vector quantity?

Posted in: CET | Date: 13/11/2017

Option D

The magnetic field intensity at any given point is specified by both a direction and a magnitude (or strength); is represented by a vector field.

• ## Question: Which is the most accurate atomic clock?

Posted in: AIEEE | Date: 13/11/2017

Option C:

According to the most accurate caesium atomic clock in the world, 1 second is the time that elapses during 9,192,631,770 cycles of the radiation produced by the transition between two levels of the caesium 133 atom

• ## Question: There are n taps connected to a tank. The efficiency of the nth tap is equa...

Posted in: Bank PO | Date: 14/11/2017

Let the time taken by the nth tap to fill up the tank be tn. The efficiency of the nth tap is equal to the sum of the efficiencies of all previous taps. i.e. the time taken by the 3rd tap= sum of the time taken by 1st and 2nd tap.

t3= t2+t1.

t4= t3+t2+t1= (t2+t1) + (t2+t1) = 2(t2+t1)

t5= t4+t3+t2+t1= 2(t2+t1)+(t2+t1) + (t2+t1) = 4(t2+t1)= 2^2(t2+t1).

؞tn= 2^(n-3)(t2+t1). the 8th tap takes 48 hours to fill the tank. ؞ t8= 2^(8-3)(t2+t1) ⇒ 2^5(t2+t1)= 48

⇒ 2^5(t2+t1) = 48

When tap number 1to9 are working together to fill the tank it will be equal to the time taken by 10th tap

2^(10-3)(t2+t1) = 2^7(t2+t1) = 2^2*t^5(t2+t1) = 4*48 = 192

Option C is the correct answer

• ## Question: The distance between the sun and the earth is r and the earth takes time T to ma...

Posted in: Physics | Date: 14/11/2017

Option C is the correct answer.

Earth (mass m) rotating around the Sun (mass M; M >> m) in a circular orbit of radius r with velocity v. Then, by applying Newton's law of gravitation and the second law of motion, we can write

Gravitational force = mass × centripetal acceleration

i.e. GMm/r2  = m(v2/r)       ... (i)

or, v2 = GM/r                 ... (ii)

The time period of rotation, T, of earth around the sun is given by,

T = 2πr/v => Squaring both sides we get, T^2= 4(πr)^2/v^2    = 4(πr)^2/GM/r = 4π^2r^3/GM .... (iii)

=> M = 4π^2r^3/GT^2      => M = K* r^3/t^2 where K is a constant equals to 4π^2/G

Hence mass of sun M is proportional to r^3/t^2

• ## Question: In the following question, two equations numbered I and II are given. Help me to...

Posted in: Bank PO | Date: 14/11/2017

i) 12p2+11p+2=0 => 12p2+3p+8p +2 = 0 => 3p(4p+1) + 2(4p+1) =0 => (3p+2)(4p+1)=0 => p = -2/3 OR p=-1/4

ii) 27q2+3q−10=0=> 27q2+18q -15q −10=0 => 9q(3q+2) -5q(3q+2) = 0 =>(9q-5)(3q+2) = 0 => q = 5/9 OR q = -2/3

p= -2/3, -1/4

q= -2/3, 5/9

Option E

• ## Question: In the given figure, O is the incentre of $$\triangle$$ PQR. PO is produced...

Posted in: AIPMT | Date: 14/11/2017

Since O is the incenter, OP is the bisector of the < QPR. Therefore <QPS= 1/2*60o =30o

Then < QRS= 30o ( Chord QS will subtend equal angle at the circumference)

and <QOR= 2*60o = 120o (angle  subtended by an arc at the centre of a circle is double the size of the angle subtended at any point on the circumference.)

Option B is the correct answer

• ## Question: Let N = 14 x 21 x 1423 x 1425.  What is the remainder when N is divided by ...

Posted in: GATE Exam | Date: 14/11/2017

Let N1, N2, N3 be numbers which when divided by a divisor D, give quotients Q1, Q2, Q3 and remainders R1, R2, R3… respectively.

Now, Remainder of  (N1X N2XN3)/D => Remainder of (R1XR2XR3)/D.

Therefore, Remainder of  (14X 21X1423X1425)/12 => (2X9X7X5)/12 => (18 X35)/12 => (6X9)/12 => 6

Option D

• ## Question: There are 60 students in a class. These students are divided into three groups A...

Posted in: GATE Exam | Date: 14/11/2017

Since we do not know the average weight of the class or average weight of each group, we cannot determine average weight of the students in group-D

Hence option D is the correct answer

• ## Question: Two railway tracks are parallel to west-east direction. Along one track, train A...

Posted in: AIPMT | Date: 15/11/2017

W→→→→→→→E

--------x--------> +ve

Train A moves from west to east positive direction. So the relative velocity of  A w.r.t to ground is Vae = +54 km/hr

Train B moves from east to west negative direction. So the relative velocity of B w.r.t to ground is Vbe = -90 km/hr

Therefore, relative velocity of B w.r.t A is Vba = Vbe + Vea = Vbe - Vae = (-90) - (+54) = -144 km/hr

= - 144*1000/(60*60) m/s = -40 m/s

Option D

• ## Question: In a group of 50 persons, everyone takes either tea or coffee. If 35 take tea an...

Posted in: AMIE | Date: 15/11/2017

option B

• ## Question: ABCD is a cyclic quadrilateral with $$\angle$$ BCD = 140°. Sides AB and DC p...

Posted in: AIPMT | Date: 15/11/2017

solution

• ## Question: In the given illustration, A, B and C are points lying on a line with B at its m...

Posted in: AMIE | Date: 15/11/2017

solution

• ## Question:  A straight wire is cut in two equal halves. One half is bent in the shape ...

Posted in: Mathematics | Date: 16/11/2017

solution

• ## Question: Radha invests Rs. 36000 for 1$$\frac{1}{2}$$year at the rate of 16% p.a. compoun...

Posted in: Mathematics | Date: 16/11/2017

A = P(1+r/n)^nt   where A=amount, P= principal, r= rate of interest in decimal, n= number of times interest compounded per year, t= time in years

A = 36000(1+0.16/2)^2*3/2 = 36000 (1.08)^3 = 36000*1.25972 = 45,349.63

Therefore, interest = Rs. A - P = 45,349.63 - 36000= Rs. 9,349.63

Option A

• ## Question: In the given figure, AB is the diameter and AC is the chord of a circle such tha...

Posted in: AMIE | Date: 16/11/2017

solution

• ## Question: Which of the following pairs of words best expresses the relationship similar to...

Posted in: GATE Exam | Date: 16/11/2017

Option C aircraft: jet

Stratosphere is a layer of the atmosphere that means it is a type of atmosphere. It is analogous to aircraft: jet, where aircraft is the category and jet, is a type of aircraft.

Nimbus: cloud is not applicable because the order is category: type whereas Nimbus is not the category but it is a type of cloud. Other options do not satisfy category:type relation

• ## Question: What sum of money should a man invest in Rs. 20 shares selling at Rs. 40 to obta...

Posted in: Mathematics | Date: 16/11/2017

Option C

Each shares (of Rs 20/-) gives 8% dividend = 8/100*20 = Rs 8/5

The man can earn Rs  8/5 from 1 shares

؞ He can earn Rs 1,000 from 1/8/5*1000 = 5000/8 = 625 shares.

Now each Rs. 20 shares is selling at Rs 40. ؞ To buy 635 shares he need to invest Rs 40 * 625 = Rs 25,000

• ## Question: A point on the pole divides in a certain ratio. Both the parts subtend equal ang...

Posted in: Mathematics | Date: 16/11/2017

Option D

• ## Question: From the given illustration, the angles of elevations of the top of a building f...

Posted in: AIPMT | Date: 17/11/2017

Let the height of the building be 'h' and and OQ be 'b'  QR = a (given)

In Δ POQ, tanx = h/b and in Δ POR tany = h/(b+a)  Therefore h= btanx...(i) and h= (a+b)tany ...(ii)

Equating (i) and (ii) we get btanx = (a+b)tany ⇒ btanx = atany + btany ⇒ btanx - btany = atany ⇒ atany = b(tanx - tany)

b= atany/(tanx-tany)   putting the value of b in (i) we get

height of the building, h= tanxtany(tanx-tany)

• ## Question: Which one of following is not the vector quantity?

Posted in: Physics | Date: 17/11/2017

Option D speed. It has only magnitude and no direction, hence it is a scalar quantity.

• ## Question: The order of magnitude of a number expressed in scientific notation is

Posted in: Physics | Date: 17/11/2017

option D

Scientific notation is the method of writing, or of displaying real numbers as a decimal number between 1 and 10 followed by an integer power of 10. In scientific notation, all numbers are written in the form of a⋅10ba⋅10b (a times ten raised to the power of b). eg 5X6X100,000 = 3,000,000  =   3.0 million.

In scientific notation, we can write it as = 3 X10^6

• ## Question: A market research group conducted a survey of 1000 consumers and reported that 7...

Posted in: Physics | Date: 17/11/2017

Total number of consumers n(AUB) =1000 Consumers who like product A, n(A) =720 Consumers who like product B ,  n(B) =450 Number of consumers who like both A and B (A∩B).

n(AUB) = n(A) + n(B) -(A∩B). ⇒  (A∩B) = n(A) + n(B) - n(AUB)

⇒ 720 +450 -1000 =1170-1000=170

Least number of people who liked both products is 170

• ## Question: A gun kept on a straight horizontal road is used to hit a car travelling on the ...

Posted in: AIPMT | Date: 17/11/2017

option A is the correct answer

• ## Question: Mr. Gupta depositsd Rs. 400 per month in a cumulative deposit account for four y...

Posted in: Mathematics | Date: 17/11/2017

Maturity value of a recurring deposit is given by  M =

R [ (1+i)n – 1] ——————– 1- (1+i) -1/3       Where, M = Maturity value R = Monthly Installment r = Rate of Interest (i) / 400 (Annual interest rate converted into quarterly rate) n = Number of Quarters (Assuming the compounding is done quarterly)                                By inputting the values given we get M= Rs21,244.00 Hence Option C is the closest to the correct answer

• ## Question: A pole consists of two parts. The lower part subtends an angle whose tangent is ...

Posted in: AMIE | Date: 18/11/2017

solution

• ## Question: Four cities are connected by a road network as shown in the figure. In how many ...

Posted in: GATE Exam | Date: 18/11/2017

option B

• ## Question: What are rules for finding significant figures?

Posted in: Physics | Date: 19/11/2017

Significant figures are the digits which give us useful information about the accuracy of a measurement

Rule 1: Non-zero digits are always significant.e.g. The number 22.22 has FOUR significant figures because all of the digits present are non-zero.

Rule 2: Any zeros between two significant digits are significant.The number 11.2 has THREE significant figures because all of the digits present are non-zero. e.g.3021 has FOUR significant figures. The zero is between a 3 and a 2.

Rule 3: A final zero or trailing zeros in the decimal portion ONLY are significant.e.g There are FOUR significant figures in 32.00. It is different from 32 It's important to understand that "zero" does not mean "nothing." Zero denotes actual information, just like any other number. we cannot tag on zeros that aren't certain to belong there.

Rule 4: Leading zeros are NOT significant. e.g The number 0.0032 also has TWO significant figures. All of the zeros are leading.

• ## Question: The length, breadth and thickness of a rectangular sheet of metal are 4.234 m, 1...

Posted in: AMIE | Date: 19/11/2017

solution

• ## Question: A pole of length ‘L’, leaning on the wall makes an angle x. When the...

Posted in: Mathematics | Date: 19/11/2017

solution

• ## Question: A light house is constructed on a cliff on the bank of a river. Height of the cl...

Posted in: AMIE | Date: 20/11/2017

option A

• ## Question: In an experiment to measure the height of a bridge, a stone is dropped into wate...

Posted in: AIPMT | Date: 20/11/2017

When the stone is dropped, the height fallen by the stone can be calculated from the formula S= ut + 1/2at^2 where s=h=height(distance), a=g =9.8 m/s2 (acceleration due to gravity), t= time and initial velocity u =0 Therefore,

h = 1/2gt^2....(i),Now error in measurement = |+/-(observed value-actual value)|.= dx. By differentiating eqn.(i) we get,

dh = 1/2*g*2tdt => dh = gtdt = 9.8*2*0.1  (since t=2, dt=0.1)

=>​ dh = 1.96 m Hence Option D

• ## Question: Assume that the total surface area of a hollow cylinder which is open from both ...

Posted in: Mathematics | Date: 20/11/2017

Since the cylinder is completely hollow and open on both sides, the curved(lateral) surface area CSA = 2πrh( r=radius of the cylinder and h=15 cm,height of the cylinder) 2πrh = 2500(given)  =>  r = 2500/2πh

Volume of the cylinder = πr^2h = π*15 *(2500/2πh)^2 = 25*25*10^4/(4*15π) = 3.315727 X 10^4 = 33157.2 cm3

Hence option A

• ## Question: In a quadrant of radius 6a, two semicircles with centers D and F are cut as show...

Posted in: AMIE | Date: 20/11/2017

Solution

• ## Question: In the given illustration, AB is the diameter of the circle with centre O. The t...

Posted in: Mathematics | Date: 20/11/2017

solution

• ## Question: A train approaches a stationary observer, the velocity of train being 1/20 of th...

Posted in: Physics | Date: 20/11/2017

Let the velocity of sound be v and the velocity of the train be u.    u =v/20 (given)

Since the blast is blown at interval of 1 second, the actual frequency of blast f=1/t = 1/1 =1 Since the train is approaching the stationary observer the apparent frequency of the blast f"= v*f/(v-u) = v*1(v-v/20) = 20/19

Apparent time interval between the blast t' = 1/f" = 19/20 s  Option C is the correct answer

• ## Question: Two boys of same height h are flying kites from a ground. The distance between t...

Posted in: Mathematics | Date: 20/11/2017

solution

• ## Question: What are the limitations of Dimensional Analysis?

Posted in: AMIE | Date: 21/11/2017

(i)            The value of dimensionless constants cannot be determined by this method. e.g. π(pi)

(ii)             This method cannot be applied to equations involving exponential and trigonometric functions.

(iii)           It cannot be applied to an equation involving more than three physical quantities.

(iv)            It can check only whether a physical relation is dimensionally correct or not. It cannot tell whether the relation is absolutely correct or not. For example, applying this technique s =ut + (1/4) at2 is dimensionally correct whereas the correct relation is s = ut + (1/2) at2

• ## Question: How can Parallax be used to measure distance to stars?

Posted in: Physics | Date: 21/11/2017

Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight and is measured by the angle or semi-angle of inclination between those two lines

To measure large distances, such as the distance of a planet or a star from Earth, astronomers use the principle of parallax. As the Earth orbits the sun, a nearby star will appear to move against the more distant background stars. Astronomers can measure a star's position once, and then again 6 months later and calculate the apparent change in position. The star's apparent motion is called stellar parallax.

There is a simple relationship between a star's distance and its parallax angle:

d = 1/p

The distance d is measured in parsecs and the parallax angle p is measured in arcseconds.

• ## Question: The nearest star to our solar system is 4.29 light years away. How much is this ...

Posted in: Physics | Date: 21/11/2017

Distance of the star is 1 lightyear (ly). 1 ly = distance traveled by light in 1 year = 3X10^8x365X24X60X60= 9.46X10^15m

I parsec(pc) = 3.08 X10^16 m  Therefore, 4.29 ly = (4.29*9.46 X10^15)/(3.08 X10^16) = 1.317  ≈ 1.32 parsec

Let θ be the parallax which the star (named Alpha Centauri) at a distance of 1.32 parsec when viewed from two locations on earth six months apart. Then θ = d/r where d  is the diameter of the earth's orbit = 2 A.U=2X1.5X10^11 (since radius of the earth's orbit = 1 AU = 1.5 X 10^11 m)

θ = d/r = arc/radius = 2 AU/1.32 parsec = 1.52

• ## Question: When the planet Jupiter is at a distance of 824.7 million kilometers from the Ea...

Posted in: Physics | Date: 21/11/2017

The question cannot be answered because the value of angular diameter is not given.

Distance of Jupiter from the earth D, 824.7 million km = 824.7 X 10^6 km = 8.247 X 10^9 m

Angular diameter = θ  Using the relation θ = D/d where d = diameter of  jupiter

d = θD = 824.7 X 10^9 θ

• ## Question: The farthest objects in our Universe discovered by modern astronomers are so dis...

Posted in: Physics | Date: 21/11/2017

Time taken by quasar light to reach earth = 3 billion years = 3.0 X 10^9 years = 3.0 X 10^9 X 365 X 24 X 60 X60

= 9.46 X 10^16 sec Speed of light = 3 X 10^8 m/s

Therefore, distance between earth and sun, d =s*t = 9.46 X 10^16 X 3 X 10^8 = 28.38 X 10^24 m = 2.8 X 10^22 km

• ## Question: A screw gauge of circular scale has a pitch of 1 mm and 200 division. By increas...

Posted in: Physics | Date: 21/11/2017

Least count = pitch/number of divisions in circular scale. Therefore, when the number of divisions in the circular scale is increased, least count will decrease and accuracy will increase (theoretically) but it is practically impossible to increase the number of divisions beyond a certain limit since the human eye cannot take accurate measurement beyond a certain limit. hence the accuracy cannot be increased beyond a limit

• ## Question: A student measures the thickness of a human hair by looking at it through a micr...

Posted in: Physics | Date: 21/11/2017

Magnification m = observed length (x)/actual length(y)  m =100, x =3.5 mm y =?

y = 3.5/100 = 0.035 mm.   Therefore, estmated thickness of human hair = 0.035 mm = 35 micrometre

• ## Question: A new unit of length is chosen such that the speed of light in vacuum is unity. ...

Posted in: Physics | Date: 21/11/2017

The problem states that speed of light in vacuum = 1 unit/sec (unity)

Distance =speed x time = 1 unit/sec x (8*60+20) sec = 500 units

Distance between the earth and sun is 500 units

• ## Question: A microscope is focused on an ink mark on the top of a table. If we place a 3 cm...

Posted in: Physics | Date: 21/11/2017

n= real depth/apparent depth  where n= refractive index of the medium

assuming refractive index of glass = 1.5 real depth = 3cm (thickness of the slab = 3cm)

therefore, apparent depth = 3/1.5 = 2 cm

Initial height of the microscope was x + 3 where x is the height of the microscope above the glass slab when no glass slab was there. Now after the glass slab is placed the new height will be x+2. So the microscope to moved by (x+3)-(x+2) = 1 cm down Option D

• ## Question: A convex lens of focal length 15 cm is placed at a distance of 20 cm from a blac...

Posted in: AIPMT | Date: 21/11/2017

Focal length of the lens f = +15 cm, image distance = +20 cm (Real image on a screen) Object distance,u= ?

from lens formula we know, 1/v-1/u =1/f => 1/u = 1/v-1/f = 1/20 - 1/15 => 1/u = (3-4)/60 =-1/60

Therefore, u = -60cm The object should be placed at 60 cms from the lens

Option D

• ## Question: A particle moves along a straight line OX. At a time t (in seconds) the distance...

Posted in: Physics | Date: 21/11/2017

The question has a mistake. If we assume the answer choices are correct, the correct equation should be

x= 40+12t-t^3 and not x= 40t+12t-t^3   When t=0, x = 40+12(0)-(0)^3 = 40m i.e. the particle has travelled 40 m at time zero

Velocity =dx/dt. When the particle comes to rest velocity will be zero. i.e. dx/dt=0 But, dx/dt = 12 -3t^2

Therefore, 12-3t^2=0 => 3t^2 = 12  => t^2 =4 => t=+/-2 (ignore -2 as time cannot be negative) Therefore, x = 40+12(2)-2^3=56m i.e. after 2 secs the body has travelled 56 m therefore, the body has travelled 56-40 =16 m before coming to rest  Option D is the correct answer

• ## Question: The force F acting on a particle of mass m is indicated by the force-time graph ...

Posted in: Physics | Date: 22/11/2017

The climate change in momentum can be calculated from the area under the force-time graph

For 0 → 2 secs,  ΔP1= 1/2(2)*6 = +6 Ns  For 2 → 4sec, ΔP2 = 2(-3) = -6 Ns  For 4 →8 sec, ΔP3 = 4(3) = =12 Ns.

So total change in the momentum from 0→8 sec = ΔP1+ΔP2+ΔP3 = 6-6+12 = 12 Ns

Option C

• ## Question: A body covers the first half of the distance between two places at a speed of 40...

Posted in: Physics | Date: 22/11/2017

Let the distance be 2d. Time taken to cover the first half of the journey, t1= distance/speed=d/40 hr and time taken to cover the second half of the journey, t2= d/60. Therefore, average speed of the car = total distance/total time= 2d/(d/40+d/60) = 2d*120/5 = 48 kmph

OptionA

• ## Question: The displacement of a particle is given by x = (t – 2) where x is in metre...

Posted in: Physics | Date: 22/11/2017

Displacement x=(t-2) where t=time. When t=0, x= 0-2 = -2 So the distance travelled = 2m in the backward direction

When t=4, x = (4-2) = 2m, distance travelled = 2m in forward direction. therefore in first 4 secs the distance travelled = 2+2=4m  Option A

• ## Question: Which of the following quantity remains constant during the uniform circular mot...

Posted in: Physics | Date: 22/11/2017

Option A  Speed

An object moving in uniform circular motion is moving around the perimeter of the circle with a constant speed. While the speed of the object is constant, its velocity is changing because at every instant direction is changing

• ## Question: The kinematic equation of motion v = u+at is not applicable if :

Posted in: Physics | Date: 22/11/2017

Option C  acceleration

The equation v = u + at is applicable only when acceleration 'a' is constant. If acceleration is changing the equation cannot be used for calculating velocity(v)

• ## Question: A ball is thrown vertically upward. At the highest point in its path, which of t...

Posted in: Physics | Date: 22/11/2017

Option A

The precise answer should be "At the highest point, vertical velocity will be zero and the direction of acceleration (due to gravity) is always vertically downward. However, at the highest point, the ball will have a horizontal velocity which will be constant throughout the path but no horizontal acceleration"

• ## Question: The motion of a freely falling body is an example of:

Posted in: Physics | Date: 22/11/2017

Option A

When a body freely falls under gravity (with no other forces acting on it, no air resistance) it is a uniformly accelerated motion where the velocity increases over time at a constant rate

• ## Question: A particle starts from rest. Its acceleration (a) varsus time (t) is as shown in...

Posted in: Physics | Date: 22/11/2017

The maximum speed will be the area under the a-t graph.

Maximum speed = area of the graph= (1/2*base of traiangle* height of triangle=1/2*11*10 = 55 m/s

Hence, option B is the correct answer

• ## Question: Two stones of different masses are thrown vertically upward with same initial ve...

Posted in: Physics | Date: 22/11/2017

The height attained by each stone can be calculated from the formula h = ut -1/2gt^2 where 'u' is the initial velocity, 't' is the time of flight and 'g' is the acceleration due to gravity (- sign because acceleration is vertically down whereas the motion is vertically up). So the height attained by each stone will depend only on initial velocity and time of flight and it is independent of mass. When both stones are thrown simultaneously with same initial velocity, they will attain equal height in equal time.

Hence option C

• ## Question: A body of mass 1kg and 10kg are dropped simultaneously from the top of a tower. ...

Posted in: Physics | Date: 22/11/2017

Let the height of the tower be H. Time 't' taken by the body to reach the ground can be calculated from the relation

t = √(2H/g) where g is acceleration due to gravity  Since the time is independent of mass, both bodies will take the same time to reach the ground

Hence option B

• ## Question: A bird is tossing (flying to and fro) between two cars moving towards each other...

Posted in: Physics | Date: 22/11/2017

The speed of car-1 is 18 km/h and the speed of car-2 is 27 km/h. Therefore, the relative speed of the cars = 18+27=45 km/h (since they are moving in opposite direction) The cars are separated by 36 km. So the time taken by the cars to meet is (distance /relative speed) = 36/45 = 4/5 hour. The bird is flying at a speed of 36 km/h from the first car.

In 4/5 hours the bird will travel 4/5*36= 144/5 = 28.8 km. The bird will cover 28.8 km when the two cars will meet.

Hence option A

• ## Question: Choose the correct answer. True or False An object in one – dimensional...

Posted in: Physics | Date: 22/11/2017

( a ) Possessing a positive value of acceleration has to be speeding up. The statement is false eg. -ve----|----  → +ve

Suppose when the car moves left to right it is +ve direction. Now if the car moves right to left and speeding up it will have a negative speed and negative acceleration, yet the car is speeding up

(b)) moving with a constant speed must have zero acceleration.  This statement is also false.

eg. An object moving in uniform circular motion is moving in a circle with constant speed but the body is accelerating because the direction of the velocity vector is changing.

(c) with zero speed at an instant may have non-zero acceleration at that instant. This statement is true.

eg When a ball is dropped from a building it starts falling with  zero speed but non-zero acceleration due to gravity

(d) possessing  zero speed could have a non-zero velocity. This statement is false. When the speed is zero, the magnitude of velocity is also zero

So the correct option should be false-false-true-false  option D

• ## Question: On a foggy day, two drivers spot in front of each other when 80 metre apart. The...

Posted in: Physics | Date: 22/11/2017

When the cars apply brakes, the distance traveled by each car before stopping be s1 and s2 respectively.

Since the stopping velocity is zero, the stopping distance can be calculated from the equation v^2- u^2 = 2(-a)s => s=u^2/2a   s1 = (70*70*10^6)/(2*5*60*60*60*60) = 37.80 m and s2 = (60*60*10^6)/(2*5*60*60*60*60) = 27.77 m

So s1+s2 = 37.80 + 27.77 = 65.57 < 80. Since the minimum distance between the car should be greater than

65.57 m (here it is 80 m) the collision can be averted.

Hence Option A

• ## Question: Rain falls at a speed of 50m/s and a child walks on a straight road from east to...

Posted in: Physics | Date: 22/11/2017

Option C. The umbrella should be held at an angle θ=tan-1(1/2)  opposite to the velocity of rain relative to the child

• ## Question: Which of the following quantity remains constant during the uniform circular mot...

Posted in: Physics | Date: 22/11/2017

option A Speed remains constant during uniform circular motion

• ## Question: The position of an object moving in a straight line can be specified with refere...

Posted in: Physics | Date: 22/11/2017

option D

• ## Question: Which one of the following is not a connective tissue?

Posted in: AIPMT | Date: 22/11/2017

Option D

Except for muscle, rest all are connective tissue. Muscle tissue is a class by itself which is distinctly different from connective tissue

• ## Question: The position of a particle is given by x = at3 where a is a constant. Help me to...

Posted in: Physics | Date: 22/11/2017

The position of the particle is given by x=at^3 The velocity (say v) of the particle at any instant is given by differentiation of its position x with respect to time as: dx/dt = v   Therefore, dx/dt = v = 3at^2

there is a typo error in the options as both options B and C are showing v=a.3/t^2

One of the options should be v=a.3t^2

• ## Question: An orange is dropped from a building. One second after dropping the orange, it f...

Posted in: Physics | Date: 22/11/2017

The height (s=stories) fallen by the orange in time (t)is given by s = ut +1/2gt^2 where u=0, initial velocity of the orange and g= acceleration due to gravity. In 1 sec after dropping the orange s = (0*1) + 1/2 g(1)^2 => s = g/2 => g=2s

When t=2, the number of stories fallen,s2 = 1/2g(2)^2   =>  s2 = 1/2(2s)(4) =4s

Therefore, 2 secs after the orange is dropped it has fallen 4 stories. Hence Option D

• ## Question: To which one of the following categories does adipose tissue belong?

Posted in: Biology | Date: 22/11/2017

Adipose tissue, or fat, is an anatomical term for loose connective tissue composed of adipocytes.

Hence adipose tissue is a type of connective tissue. Option B

• ## Question: Which one of the following types of cell is involved in making of the inner wall...

Posted in: Biology | Date: 22/11/2017

Endothelium refers to cells that line the interior surface of blood vessels. It is a thin layer of simple squamous cells called endothelial cells. Hence Option C

• ## Question: A plank with a box on it at one end is gradually raised about the other end. As ...

Posted in: Physics | Date: 23/11/2017

Option B

• ## Question: The pathogen Microsporum responsible for ringworm disease in humans belongs to t...

Posted in: Biology | Date: 23/11/2017

Option C

Microsporum belongs to the kingdom of fungi  which is the same kingdom of Rhizopus

Ascaris, a roundworm belongs to the kingdom Animalia, Wuchereria also belong to the kingdom Animalia

• ## Question:  How many functions-of stem are there? Plaese get me out of this ...

Posted in: Biology | Date: 23/11/2017

Stem has four main functions.

1. to support the leaves, flowers, and fruits. 2. to transport minerals and water to the leaves where they can be converted into usable products by photosynthesis 3. transport the synthesized food from leaves to other organs of the plant 4. storing food and water.  In some plants, stems are adapted for specialized functions.e.g.  Thorns are woody, sharply pointed branch stems

• ## Question: After the body starts moving, the friction involved with motion is

Posted in: Physics | Date: 24/11/2017

Option D kinetic friction

• ## Question: Railway tracks are banked at the curves so that the necessary centripetal force ...

Posted in: CET | Date: 24/11/2017

Option A

• ## Question: It is advised to drive along the slippery road slowly, because:

Posted in: Physics | Date: 24/11/2017

Option D

• ## Question: The time rate of change of momentum is called

Posted in: Physics | Date: 24/11/2017

Option C  Force = m*a = m*v/t (mass x velocity = momentum)

• ## Question: If newton is the unit of force in MKS system then, in CGS system 1N= ______ dyne

Posted in: Physics | Date: 24/11/2017

Option C   1 dyne = 10^(-5) N

• ## Question: The product of mass and velocity is known as

Posted in: Physics | Date: 24/11/2017

Option C   momentum

• ## Question: How is inertia used when riding a bicycle?

Posted in: Physics | Date: 24/11/2017

Option B   Even if we stop paddling due to inertia of motion we will continue to move forward  upto a certain distance as friction will finally make us stop

• ## Question: We slip on a rainy day due to

Posted in: Physics | Date: 24/11/2017

Option C  decrease in friction.

When it rains, the water forms a film between the road surface and the footwear and reduce the friction between the two surfaces and if the friction is not enough to hold the grip, we tend to slip

• ## Question: Dust can be removed out of a blanket using

Posted in: Physics | Date: 24/11/2017

Option A

When we want to remove dust from the blanket, we strike it using a rod because of which the blanket moves but the dust due to inertia of rest try to be in the same position and due to gravity now falls down

• ## Question: 98% of living body is formed of six elements, among them are- C, H,N,O and plaes...

Posted in: Biology | Date: 24/11/2017

Option B Calcium and Phosphorus

• ## Question: Please help me to find the name of the most abundant organic molecule present on...

Posted in: Biology | Date: 24/11/2017

Option D cellulose It is the most abundant organic compound on earth. It is a type of carbohydrate, containing chains of glucose rings. It provides strength and rigidity and forms the cell walls of plants. Cellulose is the primary constituent of wood, making this organic compound the most abundant one on the surface of the Earth

• ## Question: The name of the element located in centre of pophyrin ring of chlorophyll is.

Posted in: AIPMT | Date: 24/11/2017

Option D The porphyrin ring of chlorophyll, has a magnesium atom at its center, is the part of a chlorophyll molecule that absorbs light energy.

Posted in: AMIE | Date: 24/11/2017

Option D For storage, glucose needs to be converted into insoluble compound called glycogen in animals and as starch in plants.

• ## Question: What is the average cell cycle span for a mammalian cell?

Posted in: AIPMT | Date: 24/11/2017

Option C:  Approximately 24 hours

• ## Question: Each chromosome consists of __________ number of chromatid.

Posted in: AIPMT | Date: 24/11/2017

Option A

Normal body cells of diploid organisms (other than sexual reproductive cells) always contain pairs of homolog chromosomes. All these cells are genetically identical to the zygote (the product resulting from fertilization) from which they descend. One set comes from mother side and another set from father side. However, because of meiotic "reshuffling" (= crossing-overs), a different pool of genes is present in the inherited chromosomes than in the cells of the father and the mother.

Sexual reproductive cells have only one sample of each chromosome.

• ## Question: Karyokinesis is the___________.

Posted in: AIPMT | Date: 24/11/2017

Option D  Karyokinesis is the division of the nucleus, and chromosome is contained in the nucleus

• ## Question: In animal cells, the mitotic division is seen in___________.

Posted in: AIPMT | Date: 24/11/2017

Option D  In animals mitosis is only seen in diploid (having two sets of chromosomes) somatic ( any cell of living organism other than reproductive cells) cells

• ## Question: The resting phase is otherwise called as________________.

Posted in: AMITE | Date: 24/11/2017

Option B

Interphase is the interval in the cell cycle between two cell divisions when the individual chromosomes cannot be distinguished. It was formerly called the resting phase. However, interphase does not describe a cell that is merely resting; rather, the cell is actively living and preparing for later cell division, so the name was changed.

• ## Question: In animal cells, what happens during G2 phase? please, explain the answer in bri...

Posted in: AIPMT | Date: 24/11/2017

Option A

• ## Question: S phase marks like________________.

Posted in: AIPMT | Date: 24/11/2017

Option B

In the S phase (synthesis phase) during mitosis DNA is replicated. It is also a critical point during interphase when the cell duplicates its chromosome and ensures its systems are ready for cell division.

• ## Question: M phase represents__________

Posted in: AMIE | Date: 24/11/2017

Option A  M stands for mitosis

• ## Question: In which stage, the cells remain metabolically active but do not proliferate? Pl...

Posted in: AIPMT | Date: 24/11/2017

Option C    G0 phase is an inactive phase, also called as quiescent phase of the cell cycle. Cells in G0 stage remain metabolically active but do not proliferate unless called to do so depending on the requirements of the organism

• ## Question: How many chromosomes are present in each cell of onion root tip? Please, help me...

Posted in: AIPMT | Date: 24/11/2017

Option D  Onion root tip cell has 16 chromosomes in each cell.

• ## Question: The names of Lipids that are found in the cell membrane are. Plaese get me ...

Posted in: AIPMT | Date: 24/11/2017

Phospholipids are most abundant in all biological membranes. A phospholipid molecule is constructed from four components: fatty acids, a platform to which the fatty acids are attached, a phosphate, and an alcohol attached to the phosphate. Phospholipids may contain glycerol, a 3- carbon alcohol, or sphingosine, a more complex alcohol. Phospholipids derived from glycerol are called phosphoglycerides. whereas those derived from sphingosine, are called Sphingomyelin. The third group is called  Glycolipids-sugar containing lipids.

Archaeal Membranes Are Built from Ether Lipids with Branched Chains​

Cholesterol is a lipid with a structure quite different from that of phospholipids. It is a steroid, built from four linked hydrocarbon rings.​It is especially abundant in the membranes of those cells, where it helps maintain the integrity of the membranes, and plays a role in facilitating cell signaling-- meaning the ability of your cells to communicate with each other.

• ## Question: Which of the following are aromatic amino acids? Please help me to choose the co...

Posted in: Biology | Date: 24/11/2017

Option A  Phenylalanine and tryptophan are aromatic amino acids. containing an aromatic ring. Rest  B,C & Dare aliphatic

amino acids

• ## Question: The number of  carbon atoms in Arachidonic acid

Posted in: AIPMT | Date: 24/11/2017

Option A  The molecular formula of arachidonic acid is C20H32O2

• ## Question: Which is the neutral amino acid? Please get me out of this problem.

Posted in: Biology | Date: 24/11/2017

The question has an error. Except for lysine, all others are neutral amino acids. Lysine is a basic amino acid with isoelectric point 9.59

Valine has an aliphatic hydrophobic side chain whereas tyrosine and tryptophan have aromatic hydrophobic side chain

Isoelectric points are 5.96, 5.66 and 5.89 respectively

• ## Question: Which is the longest phase of meitoic division?

Posted in: Biology | Date: 24/11/2017

Option A  Prophase -I i is typically the longest phase of meiosis. During this phase homologous chromosomes pair and exchange DNA (homologous recombination).

• ## Question: The oils have which of the following?

Posted in: Biology | Date: 24/11/2017

Option C   Oils have low melting point. Oils are unsaturated. The double bonds make it harder to form a nice, compact crystal so the oils melt at a lower temperature.

• ## Question: The angle through which the outer edge is raised above the inner edge is called

Posted in: Physics | Date: 24/11/2017

option C

When a vehicle can go round the curved road at a reasonable speed without skidding, the sufficient centripetal force is generated by raising the outer edge of the road a little above the inner edge. It is called Banking of Roads.

• ## Question: In yeast the cell cycle is progressed through_______________

Posted in: AMIE | Date: 24/11/2017

Option C

• ## Question: Which law is in control of a spacecraft that cruises through space at a constant...

Posted in: Physics | Date: 24/11/2017

Option D  Newton's first Law- The law of inertia (off course we need to assume there are no interplanetary forces acting on the aircraft)

• ## Question: If the net external force on the body is zero, its

Posted in: Physics | Date: 24/11/2017

Net force on the body = mass of the body x acceleration of the body. If net force =0, acceleration=0 because mass cannot be 0 Option B or C

• ## Question: Which law governs the phenomenon that a tablecloth is pulled out from under a se...

Posted in: Physics | Date: 24/11/2017

Option A  Newton's first law- Law of inertia.

When the tablecloth is pulled the chinaware because of inertia of rest tends to stay in its place

• ## Question: In one dimensional motion, instantaneous speed v satisfies 0 ≤ v < v .

Posted in: Physics | Date: 24/11/2017

option B solution

• ## Question: What is the difference between afferent arteriole and efferent arteriole based o...

Posted in: Biology | Date: 26/11/2017

• ## Question: Plant Cytokinesis differ from animals Cytokinesis in having which of the followi...

Posted in: AIPMT | Date: 26/11/2017

Option C    Cell Plate

Plant cells divide by a cell plate that eventually becomes the cell wall whereas animal cells divide by a cleavage furrow.

• ## Question: The stage of inactivation of cell cycle due to non-availability of mitogens and ...

Posted in: AIPMT | Date: 26/11/2017

Option B

In the absence of mitogens, most cells exist in G0. The G0 phase is a period in the cell cycle in which cells exist in a quiescent state where the cell is neither dividing nor preparing to divide

• ## Question: The number of chromosome and the amount of DNA are changed in which of the follo...

Posted in: AIPMT | Date: 26/11/2017

Option A

During Anaphase, except in meiosis-I, the number of chromosomes changes (by doubling)  when sister chromatids are separated into chromosome

During the S-phase (synthesis phase) of the interphase during which DNA synthesis occurs During this phase, amount of DNA per cell doubles but the chromosome number remains the same but they exist in a structure that looks like an X shape, each chromosome contains two sister chromatid. These chromatids are genetically identical

• ## Question: If there are four chromosomes present during prophase – I, how many chromo...

Posted in: AIPMT | Date: 26/11/2017

Option A    It will have 4 chromosomes in at the end of the anaphase-II.

• ## Question: Which one proceeds reformation of nuclear envelope during M-phase of cell cycle?

Posted in: AIPMT | Date: 26/11/2017

Option C  Formation of contractile ring and phragmoplast

• ## Question: Plants show mitotic divisions in which of the following cells?

Posted in: AIPMT | Date: 26/11/2017

Option D

Plant shows mitotic divisions in both haploid and diploid cells whereas in animals mitotic division is seen only in diploid somatic cells

• ## Question: No cell could live without.

Posted in: AIEEE | Date: 26/11/2017

Option C   No cell can live without protein

• ## Question: In meiosis _______________.

Posted in: AIPMT | Date: 26/11/2017

Option A

Meiosis-II is a equational division similar to mitosis

• ## Question: A grown up cell divides when a maximum size is attained and which disturb the___...

Posted in: Biology | Date: 26/11/2017

Option A

A grown-up cell divides when a maximum size is attained and which disturb the nucleus-cytoplasm ratio (N:C ratio), also known as karyoplasmic index or Kern-Plasma ratio

• ## Question: The net charge flowing through a cross section of a conductor in unit time is kn...

Posted in: Physics | Date: 27/11/2017

Option A     Ampere

• ## Question: Two charged bodies having equal potential are connected through a conducting wir...

Posted in: Physics | Date: 27/11/2017

Option B Current will not flow

The flow of current between two charged bodies depend on the electric potential of the bodies. Current will flow only if there is a difference in the potential of the two bodies.It is analogous to heat flowing between two bodies. Heat will flow only if there is a difference in the temperature of the two bodies. Heat will not flow if both bodies are at same temperature.

• ## Question: Help me to compute 10 rational numbers between $$\sqrt 2$$ and $$\sqrt... Posted in: Mathematics | Date: 27/11/2017 ### Answer: Let √2 be 'p' and √3 be 'q' p = √2 = √(200/100) and 'q' = √(300/100) We need to find a rational number 'r' between p and q. Therefore, √(200/100) < r < √(300/100) So if we square it, then 200/100 <r2 <300/100 Let us take perfect squares between 200 and 330 like 225 and 256. By definition, rational numbers are p/q, where q= not equal to zero. Now the rational numbers r1= √225/100= 15/10 = 1.5 and r5 = √256/100 = 16/10 =1.6 so we have found two rational numbers . Let the other rational numbers be r2, r3.......r8 . So r2= (1.5 +1.6)/2 = 1.55 = 155/100 r3 = (1.5 + 1.55)/2 = 1.525 =1525/1000 Therefore, r1= 15/10, r2= 155/100. r3= 1525/1000, r5= 16/10 If we continue like this, we can easily find 10 ratioanl numbers between √2 and √3 • ## Question: Help me to find the number of zeros in the graph: Posted in: Mathematics | Date: 27/11/2017 ### Answer: The zeros of a graph ( a graph is the pictorial representation of the function) are the points where the graph of the function crosses the x-axis. In a) the graph crosses x-axis at 3 points. Hence number of zeros =3 In b) number of zeros=1 In c) number of zeros = 2 and in d) number of zeros = nil • ## Question: How do I check whether 6\(^n$$ can end with the digit 0 for any natural num...

Posted in: Mathematics | Date: 27/11/2017

If a number has to end with digit 0, the number must be a multiple of 10. i,e the number should be (10)^n where n can be 1, 2.... any positive integer. So the number must have prime factors 2 and 5.

Now, 6^n  has prime factors as 2 and 3 but not 5. Therefore, 6^n cannot be divided by 10 hence, 6^n cannot end with digit 0

• ## Question: How should I prove that $$\sqrt 5$$ is irrational?

Posted in: Mathematics | Date: 27/11/2017

It has to be proved by contradiction. Proof

• ## Question: An army contingent od 616 members is to march behind an army band of 32 members ...

Posted in: Mathematics | Date: 27/11/2017

To find the maximum numbers of columns we need to take HCF of 616 and 32

616 = 2x2x2x7x11  and 32 = 2x2x2x2x2  Therefore HCF = 8

Hence they can march in maximum 8 columns

• ## Question: A model aeroplane is tethered to a post and held by a fine line. It flies in a h...

Posted in: NEET | Date: 27/11/2017

The plane will fly in a straight line in a tangential direction to the line which was holding the plane

• ## Question: A constant force acting on a body of mass 3 kg changes its speed from 2 m/s to 3...

Posted in: NEET | Date: 27/11/2017

Initial velocity u 2.0 m/s and final velocity v = 3.5 m/s  time t =10s    mass = 3kg.

Using the relation, v = u +at we get, a = (v-u)/t = (3.5-2.0)/10 = 1.5/10 =0.15  Therefore, Force F = ma = 3*0.15 = 0.45N acting on the direction of the motion.  Hence Option C

• ## Question: Who asserted that the natural state of body is the state of rest ?

Posted in: Physics | Date: 27/11/2017

Aristotle asserted that a body was in its natural state when it was at rest

• ## Question: Two masses are in the ratio 1:5. What is ratio of their inertia?

Posted in: Physics | Date: 27/11/2017

Option A   Their inertia will also  be 1:5 as inertia is measured in terms of mass

• ## Question: When a bull pulls a cart, the force that helps the bull to move forward is the f...

Posted in: NEET | Date: 27/11/2017

When the bull pulls a cart by a force say F, the cart also pulls the bull with an equal force F in the opposite direction and the net force is zero. But the bull is also pushing the ground at an angle by a force say F1. Now the ground also pushes the bull with a force of same magnitude F1 but in opposite direction. The vertical component of the force balances with the weight of the bull and the cart but the unbalanced horizontal component of the force (if greater than frictional force) makes the bull move forward.

Hence option A

• ## Question: Why nucleus is known as the controlling center of the cell?

Posted in: Zoology | Date: 27/11/2017

The nucleus maintains the integrity of genes and controls the activities of the cell by regulating gene expression.So it is called the control center of the cell.

• ## Question: When we peel the skin of a potato tuber, we remove what part of the potato?

Posted in: AIPMT | Date: 27/11/2017

When we remove the skin of the potato tuber, we remove the periderm, a cortical protective layer of many roots and stems​

• ## Question: In five-kingdom system, the main basis of classification is.

Posted in: AIPMT | Date: 27/11/2017

Option B nutrition -autotrophic or heterotrophic. The other criteria include cell structure (complex eukaryote or simple prokaryote) thallus organization, mode of reproduction and phylogenetic relationships

• ## Question: The side of a flower facing the mother axis is called

Posted in: NEET | Date: 27/11/2017

Option B  Posterior side

• ## Question: Out of the following which one don’t provide any calories. Plaese hel...

Posted in: Biology | Date: 28/11/2017

Option A  Vitamins do not provide any calories

• ## Question: Study of muscles is called________________.

Posted in: AMIE | Date: 28/11/2017

Option B   Myology is the study of the muscular system, including the study of the structure, function and diseases of muscle

• ## Question: Muscles are attached to bones via_________________. Plaese help me to find the c...

Posted in: Biology | Date: 28/11/2017

Option A   A tendon is a tough, flexible band of fibrous connective tissue that connects muscles to bones.

• ## Question: Regurgitation is more common in infants than in adults. Plaese help me to f...

Posted in: AIPMT | Date: 28/11/2017

Option B

In older children and adults, an elastic-like muscle at the entry to the stomach closes like a valve to prevent liquids from being pushed back up. This valve or sphincter is called lower oesophageal sphincter or cardiac sphincter. In babies, however, this valve or sphincter isn't fully effective until between 6 and 12 months of age. Since it isn't fully developed yet, the valve is easily pushed back by the contents of the stomach - resulting in regurgitation or spitting up.

• ## Question:  _________________ from pharynx is conveyed into oesophagus by ____________...

Posted in: AIPMT | Date: 28/11/2017

Boluses of food from pharynx is conveyed into esophagus by Upper Esophageal Sphincter (UES)

• ## Question: In Reema’s body, substances in bile harden forming stone in the gall bladd...

Posted in: Biology | Date: 28/11/2017

Option B

Of the various conventional treatments that are available, surgical removal of the gallbladder is the most widely used.   The most commonly used surgical technique is known as laparoscopic cholecystectomy. The doctor makes several small incisions in the abdomen, then uses special pencil-thin instruments to remove the gallbladder.

• ## Question: Every cell contains DNA and when we consume plant /animal material , the DNA whi...

Posted in: Biology | Date: 28/11/2017

Option B

DNA (Deoxyribose Nucleic Acids) are digested by enzymes called nucleases which are secreted by pancreas and succus entericus (intestinal juice)

• ## Question: Intervertebral disc is found in the vertebral column of________________.

Posted in: AIPMT | Date: 28/11/2017

Intervertebral disc is found in the vertebral column of___mammals

Posted in: Biology | Date: 28/11/2017

Option B

Cardiac muscles are striated, single nucleated and involuntary

• ## Question: Regurgitation is more common in infants than in adults. The reason will be:

Posted in: Biology | Date: 28/11/2017

Option B   Cardiac sphincter is much less effective in infants

• ## Question: Read the following statements about CCK : i. this hormone stimulates gastroin...

Posted in: AIPMT | Date: 28/11/2017

OPTION C

• ## Question: People who are lactose intolerant : i. Cannot digest food with lactose in the...

Posted in: Biology | Date: 28/11/2017

Option D

People who are lactose intolerant have trouble digesting lactose, a sugar naturally found in milk and dairy products. This is because they do not have enough of an enzyme called lactase to break down lactose. Since milk is the principal source of dietary calcium, calcium supplements can help people with lactose intolerance meet their daily requirements of calcium and other important nutrients.

• ## Question: Liver stores extra glycogen but once storage limit is reached then extra carbohy...

Posted in: Biology | Date: 28/11/2017

Option D

The liver and muscle can only store a small amount of glycogen, however, so if we continue to take in more carbohydrates than needed, then our body will then convert excess carbohydrates to fat.

• ## Question: Which one of the following statement is incorrect?

Posted in: Biology | Date: 28/11/2017

Option C

The muscles located in the inner wall of alimentary canals are smooth muscles which are non-striated, involuntary, shaped like almonds (tapered ends), one nucleus per cell.

• ## Question: Parodontax toothpaste launched few months ago that help to prevent periodontal d...

Posted in: Biology | Date: 28/11/2017

Option B

The primary cause of gum disease is plaque, which is a sticky film made up of mostly bacteria.The bacteria associated with periodontal diseases are predominantly gram-negative anaerobic bacteria and may include P. gingivalis (Porphyromonas gingivalis)

• ## Question: Discovery of actin is credited to :

Posted in: Biology | Date: 28/11/2017

Option D

Actin was discovered by Straub (1942).

• ## Question: Please help me to find, a large quantity of one of the following is removed...

Posted in: Biology | Date: 29/11/2017

Option A  Carbon dioxide

• ## Question: The pH of human urine is approximately_____________.

Posted in: Biology | Date: 29/11/2017

Normal pH of urine is about 6.0

• ## Question: Dialysing unit (artificial kidney) contains a fluid which is almost same as plas...

Posted in: AIPMT | Date: 29/11/2017

Option C

Dialysis fluid does not contain urea so that urea moves across the partially permeable membrane, from the blood to the dialysis fluid, by diffusion

• ## Question: Pyruvic acid, the key product of glycolysis can have many metabolic fates. Under...

Posted in: Biology | Date: 29/11/2017

Option C  Acetyl CoA + Co2

Pyruvic acid undergoes oxidative decarboxylation to form Acetyl Co, NADH and CO2

Posted in: AIPMT | Date: 29/11/2017

Option B

Succinyl CoA + Pi + NDP ↔ Succinate + CoA + NTP

where Pi denotes inorganic phosphate, NDP denotes nucleoside diphosphate (either GDP or ADP), and NTP denotes nucleoside triphosphate (either GTP or ATP)

• ## Question: The end product of oxidative phosphorylation is______________.

Posted in: Biology | Date: 29/11/2017

Option D

32-34 ATP, H2O, NAD+, FAD are the end products of oxidative phosphorylation

• ## Question: The ultimate respiratory substrate, yielding maximum number of ATP molecules, is...

Posted in: AIPMT | Date: 29/11/2017

Option A Glycogen

Total ATP from one molecule of glucose = 30

Total ATP from one molecule of glycogen= 31

• ## Question: A particle starts from rest. Its acceleration (a) varsus time (t) is as shown in...

Posted in: Physics | Date: 30/11/2017

The above graph is an acceleration graph which gives the change in acceleration over time.

For an acceleration graph, the slope = change in acceleration/change in time = Δa/Δt (where a = acceleration, t=time) The area under an acceleration graph represents the change in velocity. In other words, the area under the acceleration graph for a certain time interval is equal to the change in velocity during that time interval.

Therefore area of the graph = Δv But we also know that a= Δv/Δt  Hence, Δv= a*Δt  = 1/2basexheight = 0.5*11*10=55 m/s. Hence the change in the velocity = 55 m/s during the time interval t=0 → t=11. Therefore the maximum velocity(V) = final velocity = initial velocity (V0)+ change in velocity (Δv)  But V0= 0 ( as the body  started from rest although it was having a positive acceleration)

So maximum velocity V = V0 + 55 = 55 m/s Option B is the corrrrect answer

• ## Question: Birds and mammals share one of the following characteristics as a common feature...

Posted in: Biology | Date: 30/11/2017

Option D

Both birds and mammals are warm-blooded, which means they can maintain a constant body temperature and do not need to rely on an external heat source to stay warm.

• ## Question: Which one of the following is oviparous?

Posted in: Biology | Date: 30/11/2017

Option A

Platypus is oviparous as it is an egg-laying mammal

Rest three are viviparous mammals

• ## Question: A body covers the first half of the distance between two places at a speed of 40...

Posted in: Biology | Date: 30/11/2017

Average speed =   2/(1/40+1/60) = 2*120/5= 48 kmph

Option A

• ## Question: Cannabis plant is used in the production of:

Posted in: Biology | Date: 01/12/2017

option  D       Charas, Ganja and marijuana  are all sourced from Cannabis  plant

• ## Question: Select the correct statement from the ones given below:

Posted in: Biology | Date: 01/12/2017

Option B is correct

Morphine still is the drug of choice for the treatment of severe acute or chronic pain.Morphine is also frequently injected to prepare for surgery and it can also be given during the operation for the suppression of nociceptive stimuli.

Although barbiturates  like sodium thiopental and amobarbital are used in an effort to obtain information from subjects who are unable or unwilling to provide it otherwise, these drugs have not been proven to cause consistent or predictable enhancement of truth-telling

Chewing tobacco does the reverse- it increases heart rate

Cocaine is never prescribed to a patient.

• ## Question: Which one of the following depresses brain activity and produces feeling of calm...

Posted in: Biology | Date: 01/12/2017

Option D

Valium (benzodiazepine) is  a CNS depressant which is used to treat anxiety

Amphetamine is a neuro stimulant. Hashsis is an illegal drug and connot be prescribed whereas morphine is a narcotic drug which is used under controlled conditions to releive moderate to severe pain

• ## Question: Division of nucleus without being followed by cytokinesis results into.

Posted in: AIPMT | Date: 01/12/2017

Option D  Multinucleate condition

A cell normally contains only one nucleus; under some conditions, however, the nucleus divides but the cytoplasm does not. This produces a multinucleate cell (syncytium) such as occurs in skeletal muscle fibres.

• ## Question: An alkaloid widely used in plant breeding for doubling the chromosome number als...

Posted in: AIPMT | Date: 01/12/2017

Option A

Colchicine, an alkaloid drug extracted from the autumn crocus is used in doubling chromosome

• ## Question: Which pigment absorbs the red and far red light?

Posted in: AIPMT | Date: 01/12/2017

Option B

Phytochromes (is a pigment found in plants) are a class of photoreceptor that plants use to detect light. They are sensitive to light in the red and far-red region of the visible spectrum and can be classed as either Type I, which are activated by far-red light, or Type II that are activated by red light.

• ## Question: Germplasm conservation at liquid N$$_2$$ temperature is

Posted in: Biology | Date: 01/12/2017

Option B

Cryopreservation means the storage of germplasm at very low temperatures by bringing the plant cell and tissue cultures to a zero metabolism or non-dividing state

• ## Question: Which of the following is a 4-carbon compound?

Posted in: Biology | Date: 01/12/2017

Option A

Oxaloacetic acid -C4H4O5

• ## Question: Which fractions of the visible spectrum of solar radiations are primarily absorb...

Posted in: AIPMT | Date: 01/12/2017

Option D

Carotenoid pigments exhibit strong light absorption in the blue portion of the visible spectrum (400 to 500 nm).

• ## Question: In chlorophyll structure four pyrole rings are united with Mg by their atoms of.

Posted in: Biology | Date: 01/12/2017

Option A    By the Nitrogen atom of the pyrole ring

• ## Question: The decomposition of organic matter is brought about by

Posted in: Biology | Date: 01/12/2017

Option C

Organic matters are decomposed by microorganisms, mainly bacteria, fungi and protozoa

• ## Question: Which one of the following is a stimulant?

Posted in: Biology | Date: 01/12/2017

Option D

Cocaine is a powerfully addictive stimulant drug made from the leaves of the coca plant native to South America.

• ## Question: Which of the following phases in mitosis is in the correct order?

Posted in: Biology | Date: 02/12/2017

Option A

Prophase ,metaphase,anaphase, telophase

• ## Question: In Photosynthesis energy from light reaction to dark reaction is transferred in ...

Posted in: AIPMT | Date: 02/12/2017

Option B  ATP

ATP is formed in the first part of photosynthesis, (light reaction). In the second part of the cycle, known as dark reactions (or Calvin Cycle), which happens in the stroma of the plant, ATP (and NADPH) combine with CO2 and H2O to make glucose. The energy required in the dark reaction comes from ATP (and NADPH)

• ## Question: Consumption of alcohol may lead to:

Posted in: Biology | Date: 02/12/2017

Option D

All of the above

• ## Question: What is Triticale?

Posted in: Biology | Date: 02/12/2017

Option A

Triticale is an intergeneric hybrid of wheat (Triticum) and rye (Secale)

• ## Question: Mutations can be induced by

Posted in: Biology | Date: 02/12/2017

Option D

Mutations can be induced in a variety of ways, such as by exposure to ultraviolet or ionizing radiation or chemical mutagens or gamma-rays

• ## Question: Dinoflagellates possess condensed chromosomes even in interphase, their nucleus ...

Posted in: AIPMT | Date: 02/12/2017

Option A

Since the nucleus of dinoflagellates (a type of algae) resemble both the ‘eukaryotes and ‘prokaryotes’, it is called ‘mesokaryotic’ nucleus. Unlike a eukaryotic cell, during cell division, in all dinoflagellates, the nuclear envelope remains intact and nucleolus does not disappear, chromosomes are permanently condensed even during interphase.

• ## Question: In C$$_3$$plants, the first stable product of photosynthesis during the dark rea...

Posted in: AIPMT | Date: 02/12/2017

Option B

The first stable compound in the Calvin cycle is a 3-carbon compound called 3-phosphoglyceric acid (PGA). Hence Calvin cycle is also called C-3 cycle

• ## Question: Etiolation in plants is caused when___________________.

Posted in: Biology | Date: 02/12/2017

Etiolation in plants occurs when they are grown in either partial or a complete absence of light. The condition is characterized by long, weak stems with smaller, sparser leaves due to longer internodes, with a pale yellow or bleached white, chlorotic colour due to lack of chlorophyll.

• ## Question: During photorespiration, the conversion of phosphoglycolate to glycolate takes p...

Posted in: AIPMT | Date: 02/12/2017

option D

Conversion of phosphoglycolate to glycolate takes place in chloroplast. 2-phosphoglycolate is converted into glycolate by the enzyme phosphoglycolate phosphatase

• ## Question: Germplasm includes

Posted in: Biology | Date: 02/12/2017

option D   All of the above is the application of germplasm

• ## Question: Which of the following terms is used to describe the component isolated from a p...

Posted in: Biology | Date: 02/12/2017

Option A

Explant culture is an in-vitro technique to organotypically culture cells from a piece or pieces of tissue or organ removed from a plant or animal.

• ## Question: Lactic acid bacteria (LAB) grow in milk and convert it to curd and also improve ...

Posted in: Biology | Date: 02/12/2017

Option D    Vitamin B12

• ## Question:  Identify the fungus with medicinal importance.

Posted in: Biology | Date: 02/12/2017

Option D

Penicillium is a genus of ascomycetous fungi of major importance in drug production. Members of the genus produce penicillin, a molecule that is used as an antibiotic, which kills or stops the growth of certain kinds of bacteria inside the body.

• ## Question: The techniques of using live organisms of enzymes from organism to produce produ...

Posted in: Biology | Date: 02/12/2017

Option D

Biotechnology deals with techniques of using live organisms OR enzymes from organisms to produce products and processes that are useful to humans. e.g. A small piece of circular DNA called a plasmid is extracted from the bacteria or yeast cell. A small section is then cut out of the circular plasmid by restriction enzymes, 'molecular scissors'. The gene for human insulin is inserted into the gap in the plasmid. Researchers return the plasmid to the bacteria and put the “recombinant” bacteria in large fermentation tanks. There, the recombinant bacteria begin producing human insulin.

• ## Question: Restriction enzymes belongs to a larger class of enzymes called?

Posted in: Biology | Date: 02/12/2017

Option A

Restriction enzyme, also called restriction endonuclease, is a group of enzyme belonging to the class nuclease, that cleaves DNA at specific sites along the molecule.

• ## Question:  DNA fingerprinting can resolve:

Posted in: Biology | Date: 02/12/2017

Option D   DNA fingerprinting can be used for all of the above

• ## Question: Who discovered recombinant DNA (rDNA) technology?

Posted in: Biology | Date: 02/12/2017

Option C

Herbert Boyer (1936-) and Stanley N. Cohen (1935-) developed recombinant DNA technology although many other scientists made important contributions to the new technology as well.

• ## Question: Which one of the following techniques made it possible to genetically engineer l...

Posted in: Biology | Date: 02/12/2017

Option B   recombinant DNA technique

• ## Question: What is the best defined function of Manganese in green plants among these optio...

Posted in: Biology | Date: 02/12/2017

Option A

In green plants,  manganese plays a very important role in the photosynthesis process by splitting the water molecule to liberate oxygen. It is absorbed in the form of manganous ions (Mn²⁺). It also plays important role in respiration and nitrogen fixation (but a majority of plant species able to form nitrogen-fixing root nodules are in the legume family) whereas photosynthesis happens in all green plants. hence option A is a better choice

• ## Question: difference between turgor pressure and wall pressure

Posted in: Biology | Date: 02/12/2017

Turgor pressure is the force within the cell that pushes the plasma membrane against the cell wall. It is the turgor pressure in the plant cells which helps the plants to be erect.

Wall pressure is the pressure exerted on the contents of a plant cell by the cell wall that is equal in force and opposite in direction to the turgor pressure.

• ## Question: Which of the following is correct sequence of process of recombinant DNA technol...

Posted in: Biology | Date: 02/12/2017

Option C

Detailed steps in recombinant DNA technology

(a) Selection and isolation of DNA segment of an insert which is to be cloned

(b) Selection of suitable cloning vector, a self-replicating DNA molecule, into which the DNA insert is to be integrated. most commonly used are plasmids and bacteriophages

(c) Fragmentation of the DNA by Restriction EndonucleaseThese are the enzymes that produce internal cuts (cleavage) in the strands of DNA, only within or near some specific sites called recognition sites/recognition sequences/ restriction sites or target sites.

(d) Then Exonuclease enzymes are used to removes nucleotides from the ends of a nucleic acid molecule.

(e) Then DNA ligase enzymes are used to join two fragments of DNA by synthesizing the phosphodiester bond

(f) Then DNA polymerases are used to synthesize a new complementary DNA strand of an existing DNA or RNA template

(g) The recombined DNA molecule is introduced into a suitable host. This process of entry of rec DNA into the host cell is called transformation

(h) Selection of transformed host cells (or recombinant cells) are those host cells which have taken up the recDNA molecule. In this step, the transformed cells are separated from the non-transformed cells by using various methods making use of marker genes

(i) Expression and Multiplication of DNA insert in the host is to be ensured that the foreign DNA inserted into the vector DNA is expressing the desired character in the host cells.

• ## Question: The enzyme pair common to C$$_3$$ plants and EMP is_______________.

Posted in: Biology | Date: 02/12/2017

Option B

Triose Phosphate Isomerase (TPI)  and Aldolase

• ## Question: In chlorophyll structure four pyrole rings are united with Mg by their atoms of.

Posted in: Biology | Date: 02/12/2017

option A    nitrogen

• ## Question: Which of the following pigments contains open pyrolle ring? Please help me to fi...

Posted in: AIPMT | Date: 02/12/2017

Option A

Phycobilins are light-capturing bilins found in cyanobacteria and in the chloroplasts of red algae. Phycobilins consist of an open chain of four pyrrole rings (tetrapyrrole) and are structurally similar to the bile pigment bilirubin,

• ## Question: At cryopreservation of germplasm, biological activity

Posted in: Biology | Date: 03/12/2017

Option D

All of the above happens in cryopreservation

• ## Question: Which one of the following microbes is used in the commercial production of etha...

Posted in: Biology | Date: 03/12/2017

Option D

Saccharomyces cerevisiae (baker's yeast) is used in commercial production of ethanol

• ## Question: Which one of the following is not used in organic farming?

Posted in: Biology | Date: 03/12/2017

Option C  Snail

• ## Question: If 10, 12 and ‘x’ are sides of an acute angled triangle, how many integer va...

Posted in: Bank PO | Date: 05/12/2017

By applying the rule, the sum of two sides of a triangle must be greater than the third side, we get 10+12 > x  =>

22 > x  =>  x <22  and  10+x >12,  =>  x > 12-10  =>x > 2  So x can take integer values between 3 and 21

But the problem states that x is the side of an acute-angled triangle. Therefore each angle < 90.

If we take one leg of the triangle as 10 and the other as 12, and the hypotenuse as x, then  12^2 + 10^2 < x^2 (since the angle has to be less than 90) i.e x^2 <244. So possible values of x^2 can be 9,16,25,36,49, 64,1,100,121,144,169, 196, 225  (13 values) The other possibility is x & 10 are the legs and 12 is the hypotenuse.

Then, x^2 +10^2  > 12^2   => x^2 > 144-100 => x^2 >44 ( Then x cannot take the values 9, 16, 25 & 36). Therefore, possible integer values of x satisfying the above conditions are 13-4 = 9 values. Hence Option C is the correct option

• ## Question: What percent of the average sales of branches B1, B2 and B3 in 2001 is the avera...

Posted in: Mathematics | Date: 05/12/2017

Data (or graph) on sales of the branches missing. The problem cannot be answered

• ## Question: The cost of carpeting a room 18 m long with a carpet 75 cm wide at Rs.4.50 per m...

Posted in: Bank PO | Date: 05/12/2017

Let the breadth of the room be 'b'  Therefore, area of the room = 18b m2.

Let 'l' be the length of the carpet.  Therfore l = total cost of carpet/ rate of carpet per metre= 810/4.5

Since the carpet covers the room completeley, area of room = area of carpet.

Therefore, 18b = (75/100)*(810/4.5)  =>  b = (75*810)/(18*4.5*100) = 7.5 m  Option B

• ## Question: If the circumradius of an isoceless triangle ABC is equal to AB (= AC), then ang...

Posted in: Bank PO | Date: 05/12/2017

We know that the circumcentre (R) of a triangle is related to the sides of a triangle ABC, with sides a,b & c by the formula

2R = a/sinA=b/sinB= c/sinC. Now R = a=c (given)

2a= a/sinA => sinA = 1/2   therfore <A=30o  since <A= <C=30o (AB=AC, given), then <B = 180-2*30 = 120= 2π/3

Option D

• ## Question: A boy goes to his school from his house at a speed of 3 km./hr and return at a s...

Posted in: Bank PO | Date: 05/12/2017

Let the distance be 'd'   Time taken for going school t1 = d/3  and time taken for coming back t2= d/2

Total time t1 + t2 = 5 Therfore d/3 + d/2 = 5 =>  5d/6 = 5  => d=6 Option C

• ## Question: A shopkeeper expects a gain of 22-1/2% on his cost price. If in a week, his sale...

Posted in: Bank PO | Date: 05/12/2017

Let C.P = Rs. 100.  profit = 22.5% Therefore S.P = Rs. 100 + 22.5/100*100 = Rs. 122.5

When SP is 122.5, profit is 22.5 When SP is Rs. 392, profit = 392*22.5/122.5 = Rs 72.0 Option C

• ## Question: A man is 24 years older than his son. In two years, his age will be twice the ag...

Posted in: Bank PO | Date: 05/12/2017

Let the present age of son be x years. Man's age is x + 24. After 2 years man's age will be x+26 and son's age will be x+2.

x+26 = 2(x+2) => x=  22  Therfore, present age of son =22 years. Option B

• ## Question: Deficiency symptoms of an element tend to appear first in young leaves. It indic...

Posted in: Biology | Date: 05/12/2017

Option A  Sulpher  deficiency results in younger leaves turning yellow first, sometimes followed by older leaves. Small, stunted plants are produced. This should not be confused with nitrogen deficiency, which appears first on older leaves and then spreads to the whole plant.

• ## Question: In a lottery, there are 10 prizes and 25 blanks. A lottery is drawn at random. W...

Posted in: Bank PO | Date: 05/12/2017

Proabability of geting prize = 10C1/35C1= 10/35 = 2/7 Option C

• ## Question: Murugan, Prasanna and Arun invested Rs.8000, Rs.4000 and Rs.8000 respectively in...

Posted in: Bank PO | Date: 05/12/2017

Investment of Murugan(M):Prasanna(P):Arun(A) = Rs. 8,000:4,000:8,000= 8:4:8

Profit of Prasanna =  (Profit X Prasanna's investment X No. of manths he invested)/(M*8 + P*8 + A*6)

= 4005*4*8/(8*8+ 4*8 + 8*6) =  4005*32/144= 890. Option A

• ## Question: Which one of the following will not directly affect transpiration?

Posted in: Biology | Date: 05/12/2017

option D

Factors affecting transpiration are light, temperature, humidity, wind and soil water

• ## Question: In how many ways a committee, consisting of 5 men and 6 women can be formed from...

Posted in: Bank PO | Date: 05/12/2017

5 men can be selected from 8 men in 8C5 ways and 6 women from 10 women can be selected in 10C6 ways.

therfore, the committee of 5 men and 6 women can be selected in 8C5 X 10C6 ways = 56 X 210 = 11,760 ways.

hence option E

• ## Question: In a healthy adult man the normal diastolic pressure is______________.

Posted in: Biology | Date: 05/12/2017

Option D Normal diastolic pressure in healthy individual is 80 mm of Hg whereas normal systolic pressure is 120 mm of Hg

• ## Question: Which of the following is not applicable for a biopatent?

Posted in: Biology | Date: 05/12/2017

Option B

On June 13, 2013, in the case of the Association for Molecular Pathology v. Myriad Genetics, Inc., the Supreme Court of the United States ruled that human genes cannot be patented in the U.S. because DNA is a "product of nature." The Court decided that because nothing new is created when discovering a gene, there is no intellectual property to protect, so patents cannot be granted. Prior to this ruling, more than 4,300 human genes were patented. The Supreme Court's decision invalidated those gene patents, making the genes accessible for research and for commercial genetic testing.

• ## Question: If the area of the quadrilateral formed by the tangents from the origin to the c...

Posted in: AMIE | Date: 06/12/2017

option D

• ## Question: An equation of the chord of a circle x$$^2$$ + y$$^2$$ = a$$^2$$ passing th...

Posted in: AIPMT | Date: 07/12/2017

Option A

• ## Question: If a body moves with velocity V in the same direction as another body moving wit...

Posted in: AIEEE | Date: 07/12/2017

Relative velocity of bodies is given by,vAB = vA−vB, where vAB  is the velocity of A respect to B,vAand vB is the Velocity of A and B respectively with reference to an observer  stationary on the ground

If we assign positive sign to one direction, the body mocing in the opposite direction will be negative.

In the problem, velocity of body-1 is V and body-2 is U. Therefore relative velocity of body-1w.r.t body-2 is

V12 = V-U (since both bodies are moving in same direction)   Option D

• ## Question: The respective ratio of radii of two right circular cylinders (A and B) is 3 : 2...

Posted in: Bank Clerical | Date: 07/12/2017

Radius of the cyliners arein the ratio of 3;2. Let the radius of cylinder-1 be 3r and the cylinder-2 be 2r. and the  height be

h1 and h2. Ratio of volume V1:V2= 9:7 Therfore    π(3r)2*h1/π(2r)2h2= 9/7  =>   9h1/4h2=9/7 =>  h1/h2= 4/7

Option B

• ## Question: In the illustrated figure below, an isosceles right-angled triangle is inscribed...

Posted in: AMIE | Date: 07/12/2017

solution

• ## Question: On a line joining the points A(0, 4) and B(3, 0), a square ABCD is constructed o...

Posted in: Mathematics | Date: 07/12/2017

Solution

• ## Question: A line meets the coordinate axes in A and B. A circle is circumscribed about the...

Posted in: AMITE | Date: 07/12/2017

solution

• ## Question: A room 5 m 44 cm long and 3 m 74 cm broad needs to...

Posted in: Bank Clerical | Date: 08/12/2017

Length of the rectangle, l = 5m44cm = 544 cm and breadth , b= 3m74cm =374 cm. If we cut the rectangle into 'x' pieces of square without any piece of rectangle left over, then x must be the HCF(highest common factor) of 544 and 374. By dividing x by the length of the rectangle we get 544/34 =16 and by divising along the breadth of the rectangle we get, 374/34=11. So the least number of sqaures that can be cut from the rectangle = 16X11 =176.    Option A

• ## Question: Please help me to find the length of the common chord of the circles (x – ...

Posted in: Mathematics | Date: 09/12/2017

solution

• ## Question: A batsman makes a score of 87 runs in the 17th inning and thus increases his ave...

Posted in: Bank Clerical | Date: 10/12/2017

Let the average score of the batsamn in 16 innings be 'x'. Therefore, total score in 16 innings is 16x. In the 17th innings he made 87 runs.Hence, the total score in 17 innings = 16+87 and the average score in 17 innings is (16x+87)/17.Since, the average has increased by 3 runs, the new average is x+3. Therfore (16x+87)/17 = x+3 =>16x+87= 17x+51 => x= 36. Hence the average after 17 innings will be 36+3=39 runs

• ## Question: A student's mark was wrongly entered as 83 instead of 63. Due to that the av...

Posted in: Mathematics | Date: 10/12/2017

Let the numbers of students in the class be 'n'. The average marks got increased by 1/2 due to the wrong-entry. Total increase = 1/2*n =n/2. Since 63 was wrongly entered as 83, difference = 20 marks. Then,n/2=20 => n=20*2=40

There are 40 students in the class

• ## Question: A large field of 700 hectares is divided into two parts. The difference of ...

Posted in: Bank PO | Date: 10/12/2017

Let the arera of the larger part be 'a' and smaller part be 'b'. Then a+b=700 and a-b=1/5*(a+b)/2 => a-b = 1/5*350 =>

a-b=70. Solving, the equations we get 2a=770 => a=385. Then b= 700-385=315  Smaller part is 315 hectares

• ## Question: In a bag, there are 6 red balls and 9 green balls. Two balls are drawn at random...

Posted in: Bank PO | Date: 12/12/2017

If we draw 2 balls at random then at least 1 red ball can be selected by  2 ways, E1 & E2..

E1= 1 ball is red and other ball is green.  E2 = both balls are red. Number of ways 1 red ball and 1 green ball can be selected is 6C1X 9C1 ways  Total number of ways by which any 2 balls can be selected is 9+6C2=15C2. Probability of E1 = 6C1X 9C1/15C2= 54/105. Number of ways 2 red balls can be selcted is 6C2 ways.Probability of E2 = 6C2/15C2= 15/105. Therefore, P(E1) + P(E2) = 54/105+15/105= 69/105= 23/35.

Option C

• ## Question: Running at the same constant rate, 6 identical machines can produce a total of 2...

Posted in: Bank Clerical | Date: 12/12/2017

6 machines can 270 botttles in 1 minute. 1 machine can produce 270/6 bottles in 1 min. 10 machines can produce 270*10/6 bottles in 1 minute. Therefore, 10 machines can produce in 4 minutes, 270*10*4/6 = 1,800 bottles Option A

• ## Question: A flagstaff 17.5 m high casts a shadow of length 40.25 m. What will be the heigh...

Posted in: Bank Clerical | Date: 12/12/2017

Height of flagstaff:Length of shadow of flagstaff = Height of building:Length of shadow of building.

Therefore, Height of the building= Height of flagstaff X Length of shadow of building./Length of shadow of flagstaff = 17.5*28.75/40.25 = 12.5 m

• ## Question: If two different numbers are taken from the set {0, 1, 2, 3, ......, 10}; t...

Posted in: Mathematics | Date: 12/12/2017

The possible combinations in the set {0,1,2....10}, whose sum and diffrence will be multiples of 4 are {0,4}, (0,8}, {6,2}, {8,4}, {10,2} and {10,6}is 6. Number of ways any 2 numbers can be picked up from the set of 11 numbers in 11C2 ways = 55 ways. Therefore, the probaliites of picking up the numbers whose sum aswell as differencein multiple of 4 is, 6/55.

Option A

• ## Question: The eccentricity of an ellipse whose centre is at the origin is $$\fra... Posted in: AMIE | Date: 12/12/2017 ### Answer: An ellipse with its centre at origin will have it foci as (c,0) and (-c,0). and having a,b as the semi-major and semi-minor axis. eccentricity of the ellipse, e = c/a=1/2(given) a=2c directrix of the ellipse,x = a2/c=-4(given) 4c2/c=-4 => c=-1; a=-2, b2=a2-c2= 4-1=3; b=√3. Then the equation of the ellipse will be x2/(-2)2+y2/3=1=> x2/4 +y2/3 =1. The equation of the normal to the ellipse at the point (x1,y1) is given by a2x/x1-b2y/y1=a2-b2 (x1=1, y1=3/2) given. Then the equation of the normal will be 4x/1-3y/3/2=4-3 => 4x-2y=1 Option B • ## Question: 39 persons can repair a road in 12 days, working 5 hours a day. In how many days... Posted in: Bank Clerical | Date: 12/12/2017 ### Answer: Person Hours/day No of days 39 5 12 1 5 12X39 1 1 12 X 39 X 5 30 6 (12 X 39 X 5)/(30X6) = 13 days Option D • ## Question: A rope can make 70 rounds of the circumference of a cylinder whose radius of the... Posted in: Bank Clerical | Date: 12/12/2017 ### Answer: Let it make n number of rounds. Since the lenght of the rope will be same in both cases, we can write the equation, 70*2π*14= n* 2π*20 ⟹ n = 7*14/2 = 49 rounds oprion A • ## Question: If the arithmetic mean of two numbers a and b, a > b > 0, is five times th... Posted in: AIPMT | Date: 13/12/2017 ### Answer: The arithmetic mean of two numbers a and b, a > b > 0, is (a+b)/2 and gemoteric mean is √ab. As per the problem, (a+b)/2=5√ab. => a+b = 2*5√ab => Squaring both sides we get, (a+b)^2 = 100ab and (a-b)^2 = (a+b)^2-4ab= 100ab-4ab => (a-b)^2 = 96ab => a-b = √96 √ab Therefore, a+b/a-b = 10√ab/ √96 √ab = 10/96 = 5/2√6 • ## Question: On a scale of a map 0.6 cm represents 6.6km. If the distance between two points ... Posted in: Bank Clerical | Date: 13/12/2017 ### Answer: Actual distance = 80.5 X 6.6/0.6 = 80.5 X 11 = 885.5 kms Option A • ## Question: A library has an average of 510 visitors on Sundays and 240 on other days. What ... Posted in: Bank Clerical | Date: 13/12/2017 ### Answer: Sundays in the given month will be on 1st, 8th, 15th, 22nd and 29th i.e. 5 sunday. Total of sunday = 510*5=2550 Total of other days = 240X25 = 6,000. Total 6000+2550= 8550. Average number of visitors per day = 8550/30=285 • ## Question: If the straight line y = mx + c (m > 0) touches the parabola y\(^2$$ = 8...

Posted in: Mathematics | Date: 14/12/2017

solution

• ## Question: The equation of a line through the point of intersection of the lines x – ...

Posted in: AIPMT | Date: 15/12/2017

The problem needs to be corrected as "distance from the origin is √5" and not the distance from the straight is

solution

• ## Question: A flagstaff stands in the centre of a rectangular field whose diagonal is 1200m ...

Posted in: AIPMT | Date: 16/12/2017

solution

• ## Question: If P and Q are the points of intersection of the circles x² + y² + 3x ...

Posted in: AIPMT | Date: 16/12/2017

Equation of the circle passing through the points of intersection of the circles S1= x2+y2+3x+7y+2p -5=0 and

S2=x2+y2+2x+2y-p2 =0 is S1+ λS2=0  where  λ ≠ (-1)  is an arbitrary real number. The circle passes through the point (1,1) Therefore, 1+1+3+7+2p-5+ λ(1+1+2+2-p2)=0   => 7+2p = λ(p2-6) =>

λ = 7+2p/(p2-6)  Now p2 can take any real value except 6, ie. p cannot take value +√6 or -√6  Option C

• ## Question: A point moves in the x-y plane according to the law x = 4 sin6t and y = 4 (1 &nd...

Posted in: AMIE | Date: 16/12/2017

Horizontal distance travelled by the particle is x= 4sin6t. Therefore, horizontal velocity = vx= dx/dt= 24cos6t.

Vertical distance travelled is y= 4(1-cos6t). Vertical velocity  vy= dy/dt= - (-24sin6t)= 24sin6t. Then the resultant velocity

v= √(vx2+vy2) = √(24^2*(sin^2(6t)+cos^2(6t)) = 24*1 = 24 m/s. Therefore distasnce travelled by the particle in 1/4 secs = 24*1/4= 6m     Option B

• ## Question: A spherical iron ball 10cm in radius is coated with a layer of ice of uniform th...

Posted in: AMIE | Date: 16/12/2017

Volume of the iron ball (spherical) coated with ice, V= 4/3πr^3.....(i) where r = (radius of the ball + thickness of ice). The rate of melting of ice at any instant, (dr/dt) can be found out by differentiating the eqn.(i)  dV/dt = 4/3*3πr^2dr/dt

=> dV/dt = 4πr^2dr/dt . r=(10+5)=15cm, dV/dt= 50 cm3/min. Therefore, dr/dt = 50/(4π*15*15)= 1/18π cm/min

Thickness of ice decrease @1/18π cm/min

• ## Question: A contract is to be completed in 56 days if 104 persons work, each working at 8 ...

Posted in: Bank Clerical | Date: 17/12/2017

There are four variables- Men(m), hours/day(h), No of days(d) and amount of job(w).

The relationship among the vraibles are as follows. mἀ1/d(inverse proportion) m ἀ 1/h (inverse proportion)

m ἀ w(direct proportion) Therefore, m = Kw/d*h, where K is a constant. hence, m1*d1*h1/w1 =m2*d2*h2/w2  =>

104X30X8/(2/5)= m2X26X9/(3/5)  (since, in 30 days 2/5th work was completed and 1-2/5=3/5th work has to be completed in 56-30=26 days ) Therefore, m2= 104X30X8X3/26X9X2 = 160. Hence, 160-104= 54 additional men needed to complete the work within 56 days working 9 hours/day

• ## Question: A man grows into a giant such that his linear dimensions increase by a factor of...

Posted in: Physics | Date: 17/12/2017

By definition stress is force per unit area. S= F/A (whereas F=mg, m, being the mass and g is grav. constant) Then S= mg/A= V*ῥ*g/A (V= volume,ῥ=density)= L^3*ῥ*g/L^2 = L*ῥ*g (where L = linear dimensions, height, breadth and depth)

Therefore, S1/S2= L1*ῥ*g /L2*ῥ*g = L1/L2  => S2= S1*L2/L1= S1*9L1/L1 => S2=9S1. Option A

• ## Question: Let k be an integer such that the triangle with vertices (k, −3k), (5...

Posted in: Mathematics | Date: 17/12/2017

solution

• ## Question: Twenty meters of wire is available for fencing off a flower-bed in the form...

Posted in: AIPMT | Date: 17/12/2017

solution

• ## Question: What can be the possible velocity displacement (v – s) graph of a particle...

Posted in: AIPMT | Date: 18/12/2017

Dispalcement of a particle under constant (non-zero) acceleration is gven by the relation s= s0+udt+1/2dt2  (s0=initial displacement, u=initial velocity, t=time and a=constant non-zero acceleration). Comparing it with the equation y=a+bx+cx2  we get the relation between displacement and time is a quadratic function and therfore the curve is a parabola. Option B

• ## Question: For three events A, B and C, P(Exactly one of A or B occurs) =P(Exactl...

Posted in: AIEEE | Date: 18/12/2017

solution

• ## Question: The average weight of 16 boys in a class is 50.25 kg and that of the remaining 8...

Posted in: Mathematics | Date: 18/12/2017

Average weight of all boys in the class = (16*50.25 + 8*45.15)/(16+8)= 11165.2/24 =48.55 kg.

• ## Question: A grocer has a sale of Rs. 6435, Rs. 6927, Rs. 6855, Rs. 7230 and Rs. 6562 for 5...

Posted in: Bank Clerical | Date: 18/12/2017

Sale in the 6th month should be Rs. 6500*6-(6435+6927+6855+7230+6562) = Rs. 4,991

• ## Question: A doctor prescribed morphine as a sedative and pain killer to your cousin who ha...

Posted in: Biology | Date: 18/12/2017

Morphine is an an opioid (also called a narcotic) analgesic, prescribed to post-sugical patients not responding to NSAIDS(Non-steroidal anti-inflammatories). Morphine is highly addictive(habbit forming). So the patient (cousin) is suffering from morphine withdrawl symptom.  Had he continued with the same medication he would have become addicted to morphine which could have finally led to morphine dependence, i.e he cannot live without daily dose of morphine.

The dose and the frequency of the morphine should be reduced gradually over a period of 1-2 weeks, However dose should not be reduced more than fifty-percent at a time and slowly tapering-off of the dose will help him to overcome morphine addiction

• ## Question: A person is born with a hereditary disease with a weakened immune system due to ...

Posted in: Biology | Date: 18/12/2017

Lack of the enzyme ADA(Adenosine deaminsae) can cause severe immunodeficiency. It is caused by mutation in the genes of x-chromosome.

The preferred treatment is bone marrow/stem cell transplantation  from an HLA-identical healthy sibling or close relative.

Second option is Enzyme replacement therapy (ERT) with polyethylene glycol-modified bovine adenosine deaminase (PEG-ADA)

The permanent cure is introducing ADAcDNA into cells at an early embryonic stage

• ## Question: A particle experiences constant acceleration for 20 s after starting from rest. ...

Posted in: AIEEE | Date: 18/12/2017

We know distance travelled s= ut + 0.5at^2, where u=initial velcity=0; as body started from rest, a=constant acceleration, t=time .  S1= (0)t+0.5a(10)^2= 50a. Volocity after initial 10 seconds,V= u +at = 0 + 10a =10a

Distance traveled in the last 10 secs, S2= v(10) + 0.5a(10)^2= 10a(10) + 50a = 150a = 3S1 Option B

• ## Question: A chord of the circle x$$^2$$ + y$$^2$$ – 4x – 6y = 0 pass...

Posted in: AMITE | Date: 20/12/2017

solution

• ## Question: The equation of a circle touching the coordinate axes and the line x cos + y sin...

Posted in: AIPMT | Date: 20/12/2017

Some data is missing in the problem. The equation of the straight line should be xcosα+ysinα=2 (alpha is missing)

solution

• ## Question: A circle C$$_1$$ of radius b touches the circle x$$^2$$ + y$$^2$$ = a$$^2$$...

Posted in: AMIE | Date: 21/12/2017

solution

• ## Question: If the area of the quadrilateral formed by the tangents from the origin to the c...

Posted in: AMIE | Date: 22/12/2017

solution

• ## Question: C$$_1$$ and C$$_2$$ are circles of unit radii with centres at (0, 0) and (1...

Posted in: AIEEE | Date: 22/12/2017

solution

• ## Question: The sum of the digits of a two digit number is 12 and when the digits of the two...

Posted in: Mathematics | Date: 26/12/2017

Let the unit digit be y and ten's digit be x. Then the number is 10x+y. and    x+y = 12 (given)....(i)

When the digits are reversed, the new number is 10y+x   Now, 10y+x= 10x+y+36  (given)  = > 9y-9x= 36

= > y-x =4 ....(ii) Solving (i) and (ii) we get,y=8, x=4 so the original number is 48. Option C

• ## Question: In the town of Windsor, 200 families have at least one car while 60 families hav...

Posted in: GRE | Date: 01/01/2018

Let A be the set of familieshaving at least one car and B be the set of families  having at least two cars.

Then the number of families having exactly one car is A'= A-B= 200-60=140

• ## Question: For how many positive integers n is it true that the sum of 13/n, 18/n, and 29/n...

Posted in: GRE | Date: 01/01/2018

13/n+18/n+29/n= 1/n(13+18+29)= 60/n. For 60/n to be an integer, n must be a factor of 60 i.e 1,2,3,4,5,6,10,12,15,20, 30,60   There are 12 positive integers

• ## Question: For how many integers n between 5 and 20, inclusive, is the sum of 3n, 9n, and 1...

Posted in: GRE | Date: 01/01/2018

3n+9n+11n>200  = > 23n>200 n>200/23 = > n>8 and n < or = 20 Between 9 and 20 (both inclusive) there are 12 integers

• ## Question: The velocity of sound waves in air

Posted in: Physics | Date: 01/01/2018

Vsound = √ɣRT/M where ɣ= adiabatic constant , R gas constant, M molecular mass of gas, T absolute tjemperature of the gas  Therefore,. Vsound is directly proportional to sqare root of absolute temeperature of air  Option D

• ## Question: As compared to sound waves frequency of radio waves is

Posted in: Physics | Date: 01/01/2018

Sound wave frequency 20 - 20,000 Hertz Radio wave frequency  20 kHz to 300 GHz Therfore, radio wave has higher frequency than sound wave. Option B

• ## Question: If the frequency of a wave 20 Hz, the time period is

Posted in: Physics | Date: 01/01/2018

T = 1 / f  = 1/20 = 0.05 secs Option D

• ## Question: The range of a cordless telephone is about

Posted in: Physics | Date: 01/01/2018

Option D

• ## Question: Signal to noise ratio of microphone is defined as the ratio of output when the s...

Posted in: Physics | Date: 01/01/2018

Option C

• ## Question: In a fascimile reproduction time to scan one line is 2 ms. If it has 4% blanking...

Posted in: Physics | Date: 01/01/2018

4% blanking means 96% the visible trace time = 0.96*2.0 = 1.92 ms Option A

• ## Question: A telephone exchange has 9000 subscribers. If the number of calls originating at...

Posted in: Physics | Date: 01/01/2018

calling rate = number of calls per subscriber = 10,000/9,000= 10/9 Option B

• ## Question: Tracking of extra terrestrial objects requires

Posted in: Physics | Date: 01/01/2018

Option D

• ## Question: A 400 W carrier is amplitude modulated with m = 0.75. The total power ...

Posted in: Physics | Date: 01/01/2018

Relation between total power and carrier power is given by  Pt = Pc (1 + m 2 /2) where Pt =Total power Pc =Carrier power m =Modulation index  Pt= 400(1+(0.75)^2/2) = 512.5 W  Option B

• ## Question: Please help me to solve the problem. A body has a positive charge of $$8 \tim... Posted in: Physics | Date: 01/01/2018 ### Answer: The elementary charge, usually denoted as e (or q) is 1.6×10−19 C Since the body has positive charge, there is a deficiency of 8 * 10-19/1.6 * 10-19 = 5.0 electrons Option B • ## Question: Circumference of a circle A is 1(4/7) times perimeter of a square. Area of the s... Posted in: Bank PO | Date: 02/01/2018 ### Answer: Circumference of circle A (whose radius is r)=1(4/7)= 11/7*4a (a being the side of a square). Area of the square = 784. Therefore, a2= 784, = > a = 28. 2*22/7r= 11/7 *4*28 (given) r = 28 Diameter of circle B is 0.5*28=14. rb= 7. Area of circle B = 22/7*7*7= 22*7= 154 sq cm • ## Question: A box contains 24 marbles, some are green and others are blue. If a marble is dr... Posted in: Bank PO | Date: 02/01/2018 ### Answer: Let the number of blue marbles be 'b' and green marbles be 'g'. P(g) = 2/3. Therefore, (gC1)/(24C1)=2/3 = > gC1= 16. Then g=16 Therefore, b= 24-16=8 There are 8 blue marbles • ## Question: Solve the differential equation: \(xdy-ydx+y^2dx=0$$

Posted in: Mathematics | Date: 02/01/2018

xdy-ydx+y2dx=0 = >    xdy = (y-y2)dx = >    dy/(y-y2) = dx/x  = >  Integrating we get    ln|y| - ln |y-1|  = ln x + lnC

= >   ln|y/(y-1)| = lnxC  = >   y/(y-1) = Cx

• ## Question: In a container, there is 960 ltr of pure milk from which 48 ltr of milk is ...

Posted in: Bank PO | Date: 02/01/2018

From 960 litres of pure milk, 48 litres is removed and replaced by water = >  fraction of milk will become (1-48/960) = 19/20 of orginal. If the process is repeated 'n' times, fraction of milk will become (19/20)^n. Since the process is repeated thrice, amount of pure milk will become (19/20)^3* 960 = 823.08 ltr. Option D

• ## Question: Both S.I. and C.I. is calculated with a similar rate of 10% per annum ...

Posted in: Bank PO | Date: 02/01/2018

Let the principal amount be Rs. 100. C.I. Amount = 100(1+0.1)^2 =  121. If C.I. = S.I., then, 121 = 100+100*(10/100)*t

= > 10t= 121-100 = >   t = 21/10 = 2.1  Option C

• ## Question: Calculate the price index number:

Posted in: Business Mathematics | Date: 02/01/2018

Solution

• ## Question: A company has two plants to manufacture bicycles. The first and second plants ma...

Posted in: AIEEE | Date: 02/01/2018

Let E1 and E2 be the event of drawing a bicycle from plant 1 & 2 respectively Let S be the event of drawing a standard bicycle.  P(E1)= 60/100 =0.6 P(E2)= 40/100 = 0.4  P(S/E1)= 80/100 =0.8 P(S/E2)= 90/100 =0.9  Since events E1 & E2 are mutually exclusice, P(standard bicycle produced by plant-2) = P(E2)* P(S/E2)/[P(E1)*P(S/E1) + P(E2)*P(S/E2)]=  0.36/0.84 = 3/7

• ## Question: Find the dimensions of the right circular cone of minimum volume that can be cir...

Posted in: Mathematics | Date: 02/01/2018

solution

• ## Question: A bill for Rs 7650 was drawn on 8 March, 2003 at 7 months. It was discounted on ...

Posted in: Business Mathematics | Date: 03/01/2018

Face value of the bill = Rs. 7,65.00 and discounted value of the bill = Rs 7,497.00 Period = 73 days (difference 18/05/2003 and 8/03/2003, both days inclusive)  Dsicount amount = 7650-7497= 153.  Rate of interest = (Interest X100)/[PrincipalXtime(yrs)](153*365*100)/(7650*73) = 10%. The banker charged 10% interest

• ## Question: A bag contains 16 eggs out of which 5 are rotten. The remaining eggs are in...

Posted in: Bank PO | Date: 03/01/2018

total no of eggs=16. No of rotten eggs=5, no of good eggs =16-5 =11. Probability of one good egg and one rotten egg  drawn is (11C1 X 5C1)/16C2 = 11 X 5 X2/16 X 15 = 11/24.  Option A

• ## Question: Find the area of the triangle whose vertices are given by $$\overrightarrow... Posted in: Mathematics | Date: 03/01/2018 ### Answer: solution • ## Question: Cost price of two beds are equal. One bed is sold at a profit of 25% and th... Posted in: Bank PO | Date: 03/01/2018 ### Answer: Let the cost price of each bed be x. Total cost price of two beds = 2x. S.P of bed-1 = 1.25x and S.P of bed-2 = (1.25x- 6596) Overall profit is 8% Then 1.25x + 1.25x- 6596 = 1.08*(2x) = > 2.5x -2.16x = 6596 = > 0.34x= 6596, = > x = 6596*100/34 = 19,400. Cost of each bed is Ts 19,400/- Option D • ## Question: If n be a positive integer,how to prove \((1+i)^n+(1-i)^n=2^{\f... Posted in: AMITE | Date: 03/01/2018 ### Answer: solution • ## Question: Find the value of ‘k’ such that x=y+k is the tangent to \(x^2=12y$$....

Posted in: Mathematics | Date: 05/01/2018

The gradiant of the curve x2=12y is dy/dx.    2xdx =12dy    = >  dy/dx = 2x/12 = x/6. Now the grandiant of the curve is equal to the gradiant of the tangent to the curve x=y+k. Rewriting the equation we get y = x-k. So the gradiant of the line is 1 (since coefficient of x=1)  Therefore, x/6=1 = >  x=6 and 12y =36, y=3. Then k = 6-3=3. Therfore, K=3 and point of contact is (6,3)

• ## Question: Solve the differential equation: $$\frac{dy}{dx}=xy+x+y+1$$

Posted in: Mathematics | Date: 05/01/2018

The given euation dy/dx= xy + x + y +1 can be rewritten as dy/dx = xy+y +y+1 = > dy/dx = y(x+1) +1(y+1) = >

dy/dx = (x+1)(y+1)  Therefore, ʃ dy/(y+1)= ʃ (x+1)dx   By integrating we get ln |y+1| = x2/2 + x +c   = >

e^(x2/2+x+c) = y+1  = >  y = e^(x2/2+x+c) - 1

• ## Question: The manufacturing cost of an item consists of Rs 900 as overheads, the material ...

Posted in: Business Mathematics | Date: 05/01/2018

Let the number of units produced is 'x'. Total Cost for producing  'x' units is Y = 900 + 3x + x2/100.  Then average cost  for  producing x units will be Y/x = 900/x+3 + x/100 By differentiating we get dy/dx= -900/x2  + 1/100 If average cost is minimum, dy/dx =0 ...(i) and d2y/dx2 = +1800/(x^3)+1/100 >0  From (i) we get  -900/x2 + 1/100 = 0 = >   900/x2 = 1/100

= >   x2 = 90000  = >   x =300 Hence the average cost will be minimum when for x=300 units.

• ## Question: A purse contains two silver and four gold coins. A second purse contains four si...

Posted in: Mathematics | Date: 06/01/2018

Probability of picking a coin from either of the two bags is 1/2. So the probability of getting a silver coin in purse1= 1/2*2/6=1/6. Probability of getting a silver coin from 2nd purse is 1/2*4/7 = 2/7. So probability of geeting a silver coin from one of the two purses is 1/6+2/7= 19/42. Similarly probability of getting a golod coin is 1-19/42= 23/42.

• ## Question: The relation between t and distance x is t=ax$$^2$$+bx where a and b are constan...

Posted in: Physics | Date: 06/01/2018

The relation between t and distance x is t=ax2+bx....(i)  Instantenous velocity = dx/dt and nstantenous acceleration= d2x/dt2. By differentiating eqn...(i) we get, dt = a(2x)dx + bdx  = >  dt = (2ax +b)dx = >  Therefore,  Instantenous velocity = dx/dt   = 1/(2ax+b) ... (ii)  By futher differentiating we get d2x/dt2 = d/dx((2ax+b)-1)  = >  (-1/(2ax+b)2)2a = >

Instantenuous accln. d2x/dt2 = -2a/(2ax+b)2*2a(dx/dt) = -2a/(2x+b)2*1/(2ax+b) = -2a/(2ax+b)3

• ## Question: Vectors can be added by

Posted in: Physics | Date: 08/01/2018

Option B  Triangular law of vector addition ( same as parallelogram law of vector addition) helps to resolve vectors into a single resulatant vector

• ## Question: Find the value of k such that $$kx^2-xy-y^2-3x+3y=0$$ represents a pair of strai...

Posted in: Mathematics | Date: 09/01/2018

General equation of a pair of straight lines is ax²+2hxy+by²+2gx+2fy+c=0. Now the given eqn may be rearranged as

kx² + 2(-½)xy+(-1)y² +2(-3/2)x+2(3/2)y+0=0 ... eqn (i) = > a=k, h= -½  b= -1   g= -3/2  f= 3/2 c=0  Eqn..(i) will represent a pair of straight lines only if abc + 2fgh – af² – bg² – ch² = 0  then k(-1)(0) +2(3/2)(-3/2)(-½) -K(3/2)²-(-1)(-3/2)²-(0)(-½)²=0

= > 0+9/4 -k(9/4) +9/4 -0 =0 = > k(9/4) = 2(9/4) = > k = 2

• ## Question: Find the equation of the parabola whose vertex and focus lie on y-axis at a dist...

Posted in: Advanced Maths | Date: 09/01/2018

solution

• ## Question: A dealer wishes to purchases a number of fans and sewing machines. He has only R...

Posted in: Business Mathematics | Date: 09/01/2018

Solution

• ## Question: Find the image of the point (1, 3, 4)on the plane x-y+z=5.

Posted in: Mathematics | Date: 10/01/2018

Solution

• ## Question: The basic difference between a scalar and vector is one of

Posted in: Physics | Date: 10/01/2018

Option B   Vector quantity has both magnitude and direction while scalar quantity has only magnitude

• ## Question: A unit vector is a vector

Posted in: Physics | Date: 10/01/2018

Option A  A unit vector is a vector of magnitude (length)= 1,  also called a direction vector

• ## Question: Vector addition is

Posted in: Physics | Date: 10/01/2018

Option A  Vector addition is commutative (does not depend on order of displacement) and also associative

• ## Question: We can define the difference of two vectors A and B as the

Posted in: Physics | Date: 10/01/2018

Option C

• ## Question: For two vectors A and B, |A + B| = |A – B| is always true when

Posted in: Physics | Date: 10/01/2018

|A+B|=|A-B| (given) Square the magnitude of the vectors. (A+B)² = (A-B)²  = >  A²+B² +2AB = A²+B²-2AB = > 4A.B=0

= > A.B =0  = |A| X |B| X cos(90) [cos(90)=0] Hence |A| and |B| are perpendicular Option B

• ## Question: The coefficient of rank correlation of marks obtained by the 10 students in Engl...

Posted in: Business Mathematics | Date: 10/01/2018

The rank co-efficient,r = 1 - 6∑d²/n(n²-1)  r=0.2, n=10 (given)   0.5 = 1 -6∑d²/10*(100-1)  = >   ∑d² = 0.5*990/6= 82.5

Corrected ∑d² = 82.5 - 3² +7² = 82.5-9+49 = 122.5. Then corrected, r = 1-6*122.5/10*99 = 1-.7424 = 0.2576.

The correct coefficient of rank of correlation is 0.2576.

• ## Question: A company has two plants to manufacture bicycles. The first and second plants ma...

Posted in: Mathematics | Date: 11/01/2018

Solution

• ## Question: Help me to find the next term in the alpha-numeric series  C4X , F9U , I...

Posted in: Bank Clerical | Date: 11/01/2018

C |D E| F |G H| I |J K| L       4    9 (5)   16(7)   25(9)    O |P Q| R |S T| U |V W| X

The next term should be  L25O

• ## Question: The word ‘Bank is derived from which of the following mentioned options:

Posted in: Bank PO | Date: 11/01/2018

Option B It came from the Italian word "banco" means bench because italian merchants made deals to lend and borrow money sitting on a bench

• ## Question: Which bank is also known as the Central bank of India?

Posted in: Bank PO | Date: 11/01/2018

Option B   (RBI)

• ## Question: Help me to find the next term in the alpha-numeric series . 2A11 , 4D13 , 12G...

Posted in: Bank Clerical | Date: 11/01/2018

4/2=2    12/4=3   48/12 =4   A |BC|D |EF|G |HI|J  11 13 (2)  17(4)  23(6)

Next term is 48J23

• ## Question: Which term comes next in the series ? DEB , IJG , NOL , ? , XYV

Posted in: Bank PO | Date: 11/01/2018

A B C D  E FG H   I J  K  L    M N  O P    Q R  S T     U  V W X   Y Z

1 2 3  4  5 6 7 8     9101112  13141516   17181920  21222324   2526

Difference between the letters of the next term in the series is 5  I-D=5, J-E=5, N-I=5

Next term in series is   STQ

• ## Question: Help me to find the next term in the alpha-numeric series . Z1A , X2D , V6G ,...

Posted in: Bank PO | Date: 11/01/2018

Z  X  V T R P ....N      A   D  G  J M P... S       1           2          6          21            88             445

(1+1)*1   (2+1)*2   (6+1)*3    (21+1)*4    (88+1)*5  .....(445+1)*6

Next term in the series N2676S

• ## Question: Help me to find the wrong number in the series. 380 , 188 , 92 , 48 , 20 , 8 ...

Posted in: Bank PO | Date: 11/01/2018

t1   t2     t3       t4     t5      t6      t7

2     8     20    48    92     188   380    t2-t1 = 6    t3-t2 =12    t4-t3 =24  t5-t4= 48  t6-t5 =96  t7-t6 = 192

t2= t1 + (t2-t1)= 2 +6   t3= t2 + (t3-t2) =8+12  ..... tn = tn-1 + (tn-tn-1)  t7 = 188+ 192=380

Hence t4 = t3+ t4-t3 = 20 +24 =44 and not 48   Hence 48 is the wrong term

• ## Question: Help me to complete the series. 120 , 99 , 80 , 63 , 48 , ?

Posted in: Bank PO | Date: 11/01/2018

120  99  80  63 48   Difference between each consecutive terms are  21  19  17 15.... 13    48-13 =35.

Hence the next term  in the series is  35  and the series will be   120  99  80  63 48 35

• ## Question: Are Kanchenjunga and k2 same?

Posted in: Geography | Date: 11/01/2018

No. K2, also known as Mount Godwin-Austen  is the second highest mountain in the world, after Mount Everest. It is located on the China–Pakistan border

Kanchenjunga is the is the third highest mountain in the world, and lies partly in Nepal and partly India (Sikkim state)

• ## Question: Find the fourth proportional to the numbers 100 : 50 : 30 : ?

Posted in: UPSC Exam | Date: 11/01/2018

100:50 : : 30:a => a= 15  Fourth proportional is 15

• ## Question: The ratio between the time taken by three cars (A, B and C) that travel the same...

Posted in: Mathematics | Date: 11/01/2018

Let hte time taken by car A be 12t and car B be 15t   Since they cover same distance VA*12t =VB*15t =>

VB = 60*12t/15t= 48 km/hr

• ## Question: Find the ratio between $$4^{3.5}$$ and $$2^5$$ : ?

Posted in: UPSC Exam | Date: 11/01/2018

4^3.5/2^5  = 2^2*3*5/2^5 = 2^30/2^5 = 2^25    Ratio= 2^25

• ## Question: What is the least 5 digit number which is perfectly divisible by 12, 25, 45 and ...

Posted in: Mathematics | Date: 12/01/2018

LCM of 12,25,45 and 60 =900. The smallest 5 digit number is 1,0000. Divide 10000/900 = 11.11. Take the next higher interger =12. Multiply 900 by 12= 10,800 the smallest 5-digit number perfectly divisible by 12,25,45 and 60

• ## Question: Find the least number which when divided by 48, 60, 72, 108, and 110, leaves the...

Posted in: UPSC Exam | Date: 12/01/2018

48-38=10,  60-50=10, 72-62=10, 108-98=10,110-100=10  The difference is 10 in all the cases.

So the required number is (LCM of 48,60,72,108,110)-10 = 23,760-10 =23,750

• ## Question: The dimensions of a room are 15.17 m and 9.02 m. The floor of the room is to be ...

Posted in: UPSC Exam | Date: 12/01/2018

Dimension of the room is 15.17 m=1517 cm and 9.02m =902 cm. The size of the square tile will be

1517,X902/(HCF of 1517,902)² = 1,368,334/41² = 814cm =8.14m  Largest possible tile should be 8.14m

• ## Question: Two numbers are in the ratio 5: 6. If their HCF is 5, then their LCM will be

Posted in: Mathematics | Date: 12/01/2018

Two numbers are in the ratio of 5:6. LCM = HCF X (Product Ratio) =5*5*6 = 150

• ## Question: Two numbers are in the ratio 3: 4 and the product of their L.C.M. & H. C. F ...

Posted in: Mathematics | Date: 12/01/2018

LCM= HCFX (Product ratio) = HCF*3*4.   LCMXHCF= 10,800 = >   HCF² = 10,800/3*4 = 900. = > HCF = 30

Then the numbers are 3*30 = 90 and 4*30=120.   Sum of the numbers are 120+90=210

• ## Question: The sum of two numbers is 192 and their HCF is 32. Find how many such pairs can ...

Posted in: Mathematics | Date: 13/01/2018

HCF of two numners is 32. So the numbers must be multiple of 32. Let the numbers be x= 32a and y=32b

x+y=192 => 32a+32b=192 a+b =192/32 =6.  The possible combinations which can give 6 are as follows. (1,5) (2,4) (3,3) (4,2) (5,1)  So 5 such pairs  can be formed

• ## Question: How many 3 digits numbers are divisible by 9 in 187, 648, 543, 837

Posted in: Mathematics | Date: 13/01/2018

A number is divisible by ( only when sim of the digits of the number is divisible by 9.

187 →   1+8+7 =25 not divisible by 9.  648  →    6+4+8 = 18 divisible by 9  543  →    5+4+3 =10 Not divisible by 9

837  →    8+3+7 =18, divisible by 9 Therfore, only two numbers among above  numbers are divisible by 9

• ## Question: The amount of alcohol in two varieties of whiskey are 27% volume/volume and 42% ...

Posted in: Mathematics | Date: 13/01/2018

If two ingredients are mixed in a ratio, quantity of cheaper/quantity of dearer= [(C.P of dearer)- Mean price]/[Mean price - (C.P of cheaper)]  Using the same a nalogy for the above problem, we get     42        27                                                                                                                                      33                                                                                                                                                                                           y          x

• ## Question: Two number are in the ratio 3 : 2. If their LCM is 240, the smaller of the two n...

Posted in: Mathematics | Date: 13/01/2018

Let the numbers be 3x and 2x. Their LCM= 6x.  6x=240 (given) x=40.  The smaller number is 2(40)=80

• ## Question: Find the number which when divides 1265 leaves quotient 84 and remainder 5

Posted in: Mathematics | Date: 13/01/2018

dividend = divisor × quotient + remainder    1265 = d* 84 +5  => 84d =1260 => d=1260/84=15. The required number is 15.

• ## Question: The product of the two prime numbers is 493. What will the L.C.M of these two nu...

Posted in: Mathematics | Date: 13/01/2018

The product of two prime number is always equal to the LCM of these two number.  Hence LCM=493

• ## Question: Find the smallest number divisible by all the odd numbers up to 15.

Posted in: Mathematics | Date: 13/01/2018

The smalles number divisible by all odd numbers upto 15 = LCM of (1,3,5,7,9,11,13,15) = 45,045.

• ## Question: Direction:- Below question is followed by two statements I and II. You have...

Posted in: Mathematics | Date: 24/01/2018

Statement -1 gives the C.P of each calculator and S.P of each calculator known. Hence we can profit from Statement -1

Statement -II gives the profit in % and S.P is known. So we can find the Profit.

Hence either statement -1 or statement -II alone is sufficient to answer the question. Option D

• ## Question: Direction: In the following question, a question is followed by information...

Posted in: Mathematics | Date: 24/01/2018

From 1 we get the number of days men will take to complete the work. Either of II or III gives the number of days women will tke to complete hte work.

Combining I and either II or III (II or III gives the same info) we get work of 1 man = work of 2 woman. Hence the question can be answered

• ## Question: Direction:- Below question is followed by two statements I and II. You have...

Posted in: Indian National Mathematical Olympiad (INMO) | Date: 24/01/2018

Statement I is not sufficient to answer the question whereas statement-II is sufficient to answer the question.  Option B

• ## Question: Which is a first generation antihistamine?

Posted in: Computer Science | Date: 25/01/2018

First generation antihistamines includes diphenhydramine (Benadryl), carbinoxamine (Clistin), clemastine (Taregyl), chlorpheniramine (Cadistin-Zydus)), and brompheniramine (Brovex, Bromaphen). These are older antihistamines and these are non- selective H1 blocker which can cross blood-brain barrier and blocks cholinergic receptors also. These agents also commonly have action at α-adrenergic receptors and/or 5-HT receptors and can produce sedation.

• ## Question: Mr Shriwardhan invested money in two schemes A and B, offering compound interest...

Posted in: Indian National Mathematical Olympiad (INMO) | Date: 24/04/2018

Rate of interest in scheme A =8% and B=9%

Every  Re. 1, invested in A after 2 years will become 1*1.08*1.08= 1.1664

And if invested in B it will become 1*1.09*1.09= 1.1881.

If we convert it to simple interest, S.I for A =16.64/2= 8.32% and for B=18.81/2= 9.405%

Total interest on Rs. 27,000 for 2 years is Rs. 4818.3

Effective S.I= 4818.3/27,000*100/2=8.923%, which is the weighted average of the schemes A&B.

By applying allegation rule we get,

(B)9.405                  8.32(A)

8.923

0.603              :                 0.487

Therefore, amount invested = 0.482/(0.482+0.603)*27,000= 11,944 (round off to) Rs.12,000

• ## Question: Four sheets of 45 cm × 5 cm are to be arranged in such a manner that they ...

Posted in: Indian National Mathematical Olympiad (INMO) | Date: 24/04/2018

Since the 4 strips has to be arranged in a square, each side of the square will be √(4X45X5) = 30  cm

So the area of the 4  strips is 30X30= 900 cm2

• ## Question: 3 litres of liquid M is taken and mixed with 5 litres of liquid N. The mixture i...

Posted in: Indian National Mathematical Olympiad (INMO) | Date: 24/04/2018

M=3 litres N= 5 litres. Divided into 4 equal parts. so in each part M=(1/4)*(3/8) and N= (1/4)*(5/8) Now 'x' amount of M is added to one part. Therefore, (1/4)*(3/8)+x/(1/4)*(5/8)= 6/5 => 3+4x/5= 6/5 => 4x=3 => x=3/4. (3/4 litres M is added)

New ratio of M/N= (3+3/4)/5= 15/20 = 3/4  Hence M:N = 3:4

• ## Question: A, B and C are three partners. A and B have money in the ratio 7: 17 and B and C...

Posted in: Mathematics | Date: 24/04/2018

A/B= 7/17 and B/C= 7/17 Therefore A/B/C = 7*7/17*7/17*17 = 49/119/289 (By taking LCM of the values of B)

But A=4900(given) therfore C= 28,900

• ## Question: The price of a bike is increased by 25%, by how much percent, must the new price...

Posted in: Mathematics | Date: 24/04/2018

Let the price of the bike be Rs 100. If the price is increased by 25% the new price will be 100+25/100*100=Rs 125.

To restore the original price, the price must be decreased by Rs 25 which is 25/125*100= 20%

• ## Question: One fourth of a journey is covered at the rate of 50 km/h, one third at the rate...

Posted in: Mathematics | Date: 24/04/2018

Average speed = 1/[1/4/50+1/3/60+{1-(1/4+1/3)/100}]=1/[1/200+1/180+5/1200]= 1/[53/3600]= 3600/53=67.92 km/hr

• ## Question: Four numbers in the ratio 1 : 2 : 5 : 7 add to give a sum of 135. Find the value...

Posted in: Mathematics | Date: 26/04/2018

Biggest number = 7(1+2+5+7)*135= 7/15*135= 63

• ## Question: 7 kg of rice costing Rs. 280 per kg is mixed with 9 kg of rice costing Rs. 240 p...

Posted in: Mathematics | Date: 26/04/2018

By aligation method

280 ↘       ↙   240

x

7    ↙       ↘ 9     =>   9/7 = (280-x)/(x-240)  =>   16x= 4120  => x= 4120/16= 27.50

Average price of per kg mixed rice is Rs. 27.50

• ## Question: A mixture A (20 litres) and B (40 litres) of water: milk ratio 1: 1 and 2 : 3&nb...

Posted in: Mathematics | Date: 26/04/2018

In mixture -1, water part = 1/2 and in mixture-II, water part is 2/5. After  mixing, water part in the new mixture  will be

1/2        2/5

x   = water part  =>  2= (0.5-x)/(x-0.4)  => 2x-0.8 = 0.5-x => 3x= 1.3  => x= 13/30 Therfore milk part will be (30-13)/30

20    :    40                =17/30   Therfore in the new mixture  ratio of water:milk= 13;17

• ## Question: Two kinds of rice are sold at the same price in which 10% is gained on one kind ...

Posted in: Mathematics | Date: 11/05/2018

Let S.P. of both types of rice (R1 & R2) be Rs.100 per kg. On R1, 10% profit and on R2 10% loss incurred.

C.P of R1= (100/1.1)=Rs.90.9/kg  and C.P of R2 = (100/0.9)=Rs.111.11./kg.

S.P of 1 Kg of R1 + 1 kg of R2 = 90.9+111.11= Rs. 202.00 Profit = 200-202 = -2 (loss of Rs 2)

% loss 2/202*100 = 0.99 approx 1%

• ## Question: Taniya sells a watch at a gain of 15%. If she had bought it at 10% less and sold...

Posted in: Mathematics | Date: 11/05/2018

Let the C.P of the watch be Rs 100. Sold for 15% profit. Therfore S.P =115.  If she had purchased for 10% less the then

C.P(new) = Rs. 90 and sold for 20% profit. S.P(new) = 1.2*0.9 =108  Therfore he she should have sold for Rs (115-108)=

Rs 7 less.But actually she sold for Rs 3.5 less(1/2 of the assumed value). Therefore, actaul price of the watch was Rs 50(1/2 of the assumed value)

• ## Question: Harrison has two weights of one kilogram at his shop. One of the weights is accu...

Posted in: Mathematics | Date: 12/05/2018

S.P= C.P ( goods sold at cost price.) Let C.P and S.P of 1 kg(=1000 gms) of goods be Re 1.

When Harrison picks the wrong weight, he sells 1100 gms but takes price for only 1000 gms.

When he picks up the wrong weight his C.P(wrong),will be Rs 1.10  but S.P still be Rs 1.0

Probability of picking wrong weight is 3/5 and right weight is 2/5.

So his average cost price (x)can be found out by applying allegation technique.

1.1      1.0

x

3/5           2/5            2/5:3/5= (1.1-x):(x-1.0) => 2x-2 = 3.3- 3x => 5x = 5.3 => x= 5.3/5

Average C.P = 5.3/5 and S.P=1, Loss% = (1-5.3/5)/(5.3/5)*100=> 0.3*100/5.3 =5.66%

• ## Question: A dishonest dealer sells his goods at the cost price but still earns a profit of...

Posted in: Mathematics | Date: 12/05/2018

Let S.P= C.P = Rs .100. Since the seller is making profit, he is selling less quantity for every 1 kg.

Since he is making 28% profit, his actaul cost price is Rs 100/1.28 = Rs .78.125.

For Rs. 100, he can buy 1000 gms. For Rs 78.125, he buys  78.125/100*1000= 781.25 gms.

Therfore he uses 781.25 gms weight for every Kg

• ## Question: In a fixed time, a man swims double the distance along the current that he swims...

Posted in: Mathematics | Date: 12/05/2018

Let the speed of the man in still water be x km/hr and time be t hours

Relative Speed downstream = x+3 and upstream = x-3.

Since the downstream distance is double the upstream distance

(x+3)*t = 2(x-3)*t => x+3 = 2x-6 => x=9.

Speed of the man in still water is 9 km/hr

• ## Question: Mohan purchased 25 kg of sugar at Rs. 30 per kg and mixed it with 15 kg of sugar...

Posted in: Mathematics | Date: 12/05/2018

36             30

x

15             25         C.P of the mixture (x) =>25/15= (36-x)/(x-30) =>  5(x-30) = 3(36-x) => 5x-150 = 108-3x =>

x=258/8 = 32.25 Therfore, S.P. =1.1X32.25(10% profit over C.P)= Rs.35.47

He should sell I kg of mixture at Rs 35.47

• ## Question: An alloy contains copper and zinc in the ratio of 4:3 and another contains coppe...

Posted in: Mathematics | Date: 12/05/2018

For Alloy-1, C:Z=4:3  C= 4/7  In 14 kg of alloy-1, 8 kg copper   For alloy-2, C:T =9:5   In 14 kg of alloy-2, 5 kg tin. When equal weights of two alloys are mixed together, in 28 kg of new alloy, 5 kg of tin. Therfore, in 1 kg of new alloy, 5/28 kg tin.

• ## Question: A car starts from rest and attains a speed of 8 metre per second in 2 seconds wi...

Posted in: Physics | Date: 15/05/2018

Initial velocity 'u'=0, final velocity 'v'= 8 m/s. acceleration ='a'  Acceleration time 't1'= 2 s Uniform speed travel time 't2'=3

Diispalcement during acceleration ='s'  and during uniform speed = s1.

v=u + at => 8 = 0 + a(2) => a= 8/2 = 4m/s²     s= ut +0.5 at² => s= 0 + 0.5*4*2²= 8 m S1= 8*3=24m

Total dispalcement = s+s1= 8+24=32m

• ## Question: Why is ice at zero degree celsius more effective in cooling than water at zero d...

Posted in: Chemistry | Date: 15/05/2018

Ice at zero degree needs latent heat  of 334 joules per gram  of ice to convert into water at same temperature ( zero degree)

Since ice can absorb this heat from the enivironment, it has more cooling effectiveness compared to water at same temperature

• ## Question: What temperature in Kelvin scale is equal to 60 degree celsius

Posted in: Chemistry | Date: 15/05/2018

T(°C) = T(K) - 273.15 => T(K)= 60+273.15= 333.15°K