### Anita M Female, 23 Years

Associated for 5 Years 6 Months
Basic Computer / Office Tutor

#### Activity Score - 2845

• I teach at My Home
• Online
Area: Kidwai Nagar
Location: Rajkot, India
Qualification :
• M.Com (Saurashtra University - 2015)
• Hourly Fees:
INR 250
Tutoring Experience :

I don't have any such professional teaching experience but if given a chance, I would be able to bring out the best from my students as I believe that if the concept and basic is cleared then learning any topic will be much more easier and fun for students.

Tutoring Option :
Online Tuition Only
Tutoring Approach :

I plan the lessons as per the student's ability to cop up and and moreover upon their needs. My teaching technique is student friendly and easy to understand which helps student understand it better. Weekly tests will be conducted to know the student's performance.

Teaches:
 Nursery Level All Subjects Reading Skills Writing Skills Counting Skills INR 100 / Hour Class 1 - 5 Mathematics English Geography All Subjects CBSE Board INR 200 / Hour Languages English Hindi Gujarati INR 200 / Hour Class 6 - 8 Mathematics Accountancy School level computer Commerce Subjects CBSE INR 300 / Hour Basic Computer / Office Basic Computer School level computer Tally ERP 9 MS Office INR 250 / Hour
• ## Question: what is trigonometry

Posted in: Mathematics | Date: 05/12/2017

Trigonometry is a branch of mathematics that studies relationships involving lengths and angles of triangles. All of the trigonometric functions of an angle θ can be constructed geometrically in terms of a unit circle centered at O.

• ## Question: Which of the following is an advantage of transgenesis?

Posted in: NEET | Date: 05/12/2017

D. All of above

• ## Question: Bt toxin is coded by which gene?

Posted in: Biology | Date: 05/12/2017

A. Cry

• ## Question: What is Acrylic Painting?

Posted in: Acrylic Painting | Date: 05/12/2017

Acrylic paint is a fast-drying paint made of pigment suspended in acrylic polymer emulsion. Acrylic paints are water-soluble, but become water-resistant when dry. Depending on how much the paint is diluted with water, or modified with acrylic gels, media, or pastes, the finished acrylic painting can resemble a watercolor or an oil painting, or have its own unique characteristics not attainable with other media.Acrylic paint is typically used for crafting, or in art classes in schools because it does not require any chemicals, and rinses away with just water. It also is less likely to leave a stain on clothes than oil paint.

• ## Question: Who wrote Look Back In Anger ?

Posted in: English | Date: 05/12/2017

John Osborne

• ## Question: Who wrote The Secret Sharer ?

Posted in: English | Date: 05/12/2017

• ## Question: One of the common symptoms observed in people infected with Dengue fever is.

Posted in: AIPMT | Date: 05/12/2017

C. Significant decrease in platelets count. In classical dengue fever, it usually starts to fall by 3 days, most significant by 5 days and comes back to normal (if no complications arise)by 11 days.

• ## Question: During photorespiration, the conversion of phosphoglycolate to glycolate takes p...

Posted in: AIPMT | Date: 06/12/2017

D. Chloroplast. Conversion of phosphoglycolate to glycote takes place in chloroplast. Photorespiration is the uptake of O2and release of CO2in light that results from the biosynthesis of glycolate in chloroplast and subsequent metabolism of glycolic acid in the same leaf cell through other two cell organelles (peroxisome and mitochondria).

• ## Question: Which fractions of the visible spectrum of solar radiations are primarily absorb...

Posted in: Biology | Date: 06/12/2017

D. Violet and blue The visible spectrum of solar radiations are primarily absorbed by carotenoids of the higher plants are violet and blue.

• ## Question: Crystals of Bt toxin produced by some bacteria do not kill the bacteria themselv...

Posted in: AIPMT | Date: 06/12/2017

C. toxin is inactive: In bacteria, the toxin is present in an inactive form, called prototoxin, which gets converted into active form when it enters the body of an insect.

• ## Question: A thin glass (refractive index 1.5) lens has optical power of -5D in air . ...

Posted in: Physiology | Date: 06/12/2017

A.1D

• ## Question: The total age of A and B is 12 years more than the total age of B and C. C ...

Posted in: Bank Clerical | Date: 07/12/2017

(A+B)-(B+C)=12, A-C=12 Therefor, C is younger than A by 12 years....

• ## Question: One year ago, the ratio of Sooraj's and Vimal's age was 6:7 respect...

Posted in: Bank Clerical | Date: 07/12/2017

ratio sooraj vimal 1- 6 7 diff 1 4+ 7 8 diff 1 multiply them with others diff 1- 6:7 4+ 7:8 take diff of anyofthem 7-6=1 8-7=1 actully -1+4=5 years is diff multiply all answers with 5 1- 30 35 5+ 35 40 so vimal now is35+1=36 or40-4=36

• ## Question: The product of the ages of Syam and Sunil is 240. If twice the age of Sunil...

Posted in: Mathematics | Date: 07/12/2017

Let Syam=x Sunil = y , According to question, x/y= 240.......(1) 2y-x= 44........(2). x=240/y.. Solving eq. (1)&(2)... 2y-240/y=4. y2-120=2y. y2-2y-120=0. y2-12y+10y-120=0 Y(y-12)+10(y-12). (y-12) (y+10). Y= 12, -10.. Therefor... Y= 12 years. So, Sunil's age would be 12years

• ## Question: The ratio of the age of a man and his wife is 4:3. At the time of marriage ...

Posted in: Mathematics | Date: 07/12/2017

D. 12 years Solution...Let the present age of the man and his wife be 4 x 4x and 3 x 3x respectively. After 4 4 years this ratio will become 9 : 7 97 ⇒ ( 4 x + 4 ) : ( 3 x + 4 ) = 9 : 7 ⇒ 7 ( 4 x + 4 ) = 9 ( 3 x + 4 ) ⇒ 28 x + 28 = 27 x + 36 ⇒ x = 8 4x43x497 74x493x4 28x2827x36 x8 Present age of the man = 4 x = 4 × 8 = 32 4x4832 Present age of his wife = 3 x = 3 × 8 = 24 3x3824 Assume that they got married before t t years. Then, ( 32 − t ) : ( 24 − t ) = 5 : 3 ⇒ 3 ( 32 − t ) = 5 ( 24 − t ) ⇒ 96 − 3 t = 120 − 5 t ⇒ 2 t = 24 ⇒ t = 24 2 = 12

• ## Question: If 6 years are subtracted from the present age of Ajay and the remaind...

Posted in: Bank Clerical | Date: 07/12/2017

Present age of Denis = 55 years Present age of Rahul = 55 − 22 = 33 Let present age of Ajay = x x Then, present age of Rahul = x − 6 18 x618 x − 66 18 = 33 ⇒ x − 6 = 3 × 18 = 54 ⇒ x = 54 + 6 = 60

• ## Question: Kamal was 4 times as old as his son 8 years ago. After ...

Posted in: Mathematics | Date: 07/12/2017

Explanation: Let age of the son before 8 8 years = x x Then, age of Kamal before 8 8 years ago = 4 x 4x After 8 8 years, Kamal will be twice as old as his son ⇒ 4 x + 16 = 2 ( x + 16 ) ⇒ x = 8 4x162x16 x8 Present age of Kamal = 4 x + 8 = 4 × 8 + 8 = 40 4x848840

• ## Question: Present age of a father is 3 years more than three times the age of hi...

Posted in: Bank Clerical | Date: 07/12/2017

Let the present age the son = x Then, present age of the father = 3 x + 3 Given that, three years hence, father's age will be 10 10 years more than twice the age of the son ⇒ ( 3 x + 3 + 3 ) = 2 ( x + 3 ) + 10 ⇒ x = 10 3x332x310 x10 Father's present age = 3 x + 3 = 3 × 10 + 3 = 33

• ## Question: The ages of two persons differ by 16 years. 6 years ago, the elde...

Posted in: Mathematics | Date: 07/12/2017

C. 30. Explanation: Let present age of the elder person = x x and present age of the younger person = x − 16 x16 ( x − 6 ) = 3 ( x − 16 − 6 ) ⇒ x − 6 = 3 x − 66 ⇒ 2 x = 60 ⇒ x = 60 2 = 30

• ## Question: If the density of lake water is 1.25 g mL$$^{-1}$$ and it contains 92 g of Na$$^... Posted in: Chemistry | Date: 07/12/2017 ### Answer: Density of lake water = 1.25 g mL-1 Amount of Na+ ion in one kg of water = 92 g Atomic mass of Na+ = 23 g mo1-1 Let V ml of lake water be taken. Let take mass of solvent(water) = 1 Kg Then mass of Na+ ions = 92 g Number of moles of = 92/23 = 4 (molar mass of Na is 23g/mol) Plug the values we get Molality = 4 /1 = 4m Solution molality of Na + ions = 4m • ## Question: The age of father 10 years ago was thrice the age of his son. Ten years hen... Posted in: Mathematics | Date: 07/12/2017 ### Answer: Let the ages of father and son 10 years ago be 3x and x years respectively. Then, (3x + 10) + 10 = 2[(x + 10) + 10] 3x + 20 = 2x + 40 x = 20. Required ratio = (3x + 10) : (x + 10) = 70 : 30 • ## Question: Sobha's father was 38years of age when she was born while her mother wa... Posted in: Bank PO | Date: 07/12/2017 ### Answer: Mother's age when Sobha's brother was born = 36 years. Father's age when Sobha's brother was born = (38 + 4) years = 42 years. Required difference = (42 - 36) years = 6 years. • ## Question: A is as much younger than B and he is older than C. If the sum of the ages of B ... Posted in: Bank PO | Date: 07/12/2017 ### Answer: A. Data inadequate... Explanation: B- A = A- C (B+ C) = 2A Now given that, (B + C) = 50 So, 50 = 2Aand therefore A= 25. Here we know the value(age) of A (25), but we don't know the age of B Therefore, (B-A) cannot be determined. • ## Question: A person's present age is two-fifth of the age of his mother. After 8&n... Posted in: Mathematics | Date: 07/12/2017 ### Answer: C. 40. Let the mother's present age be x years. Then, the person's present age = 2 x years. 5 2 x + 8 = 1 (x + 8) 5 2 2(2x + 40) = 5(x + 8) x = 40. • ## Question: How can I explain alkylamine is more basic than ammonia? Posted in: Chemistry | Date: 07/12/2017 ### Answer: The basicity of amines depends on the +I effect of the alkyl groups. With increase in alkyl group the +I effect will increase which will increase the ease of donation of lone pair electron. Amine will accept a proton and from cation will be stabilized in water by salvation (by hydrogen bonding).better the salvation by hydrogen bonding higher will be the basic strength. Hence, alkyl amine is more basic than ammonia CH3NH2 > NH3 • ## Question: The present ages of A,B and C are in proportions 4:7:9. Eight years ago, th... Posted in: Bank Clerical | Date: 07/12/2017 ### Answer: Let their present ages be 4x, 7x and 9x years respectively. Then, (4x - 8) + (7x - 8) + (9x - 8) = 56 20x = 80 x = 4. Their present ages are 4x (a)= 16 years, 7x(b) = 28 years and 9x(c) = 36 years respectively. • ## Question: Chromium metal crystallises in a body centred cubic lattice. The length of the u... Posted in: Chemistry | Date: 07/12/2017 ### Answer: Answer : 7.30gcm−37.30gcm3 In a body-centred cubic lattice ,atoms touch each other along the body-diagonal of the cube.Hence 4r=3–√a4r3a or r=3–√a4=(1.732)(287pm)4=r3a41.732287pm4124.27124.27pm. The expression of density is ρ=Na3(MNA)ρNa3MNA Substituting the values,we get ρ=2(287×10−10cm)3(51.99gmol−16.023×1023mol−1)ρ22871010cm351.99gmol16.0231023mol1=7.30 • ## Question: My brother is 33 years elder to me. My father was 28 years of age... Posted in: Bank Clerical | Date: 07/12/2017 ### Answer: D. 32 years FFather's age was 28 28 years when my sister was born. My sister's age was 4 4 years when my brother was born. Therefore, father's age was 28 + 4 = 32 32 years when my brother was born. • ## Question: An aqueous solution containing 28% by mass of liquid A (molecular mass = 140) ha... Posted in: Chemistry | Date: 07/12/2017 ### Answer: For total miscible liquids, Ptotal = Mol. fraction of A × pA0 + Mol. fraction of B × pB0 No. of moles of A = 28/140 Liquid B is water. its mass is (100−28), i.e., 72. No. of moles of B = 72/18 Total number of moles = 0.2 + 4.0 = 4.2 Given, Ptotal = 160 mm pB0 = 150 mm So 160 = 0.2/4.2 × pB0 + 4.0/4.2 × 150 pA0 = 17.15×4.2/0.2 = 360.15 mm • ## Question: At present, the ratio between the ages of Shekhar and Shobha is 4:3. After&... Posted in: Bank Clerical | Date: 07/12/2017 ### Answer: Answer: Option A Explanation: After 6 6 years, Shekhar's age will be 26 26 years Therefore, Present age of Shekhar = 26 − 6 = 20 26620 Let present age of Shobha = x x Then, 20 x = 4 3 x = 20 × 3 4 = 15 • ## Question: Six years ago, the ratio of the ages of Vimal and Saroj was 6:5. Four years... Posted in: Mathematics | Date: 07/12/2017 ### Answer: Answer: Option C Explanation: Given that, six years ago, the ratio of the ages of Vimal and Saroj = 6 : 5 65 Hence we can assume that age of Vimal six years ago = 6 x 6x age of Saroj six years ago = 5 x 5x After 4 4 years, the ratio of their ages = 11 : 10 1110 ⇒ ( 6 x + 10 ) : ( 5 x + 10 ) = 11 : 10 ⇒ 10 ( 6 x + 10 ) = 11 ( 5 x + 10 ) ⇒ 5 x = 10 ⇒ x = 10 5 = 2 Saroj's present age = ( 5 x + 6 ) = 5 × 2 + 6 = 16 • ## Question: The sum of the present ages of a son and his father is 60 years. Six years ... Posted in: Mathematics | Date: 07/12/2017 ### Answer: Option D Explanation: Let the present ages of son and father be x and (60 -x) years respectively. Then, (60 - x) - 6 = 5(x - 6) 54 - x = 5x - 30 6x = 84 x = 14. Son's age after 6 years = (x+ 6) = 20 years.. • ## Question: Kiran is younger than Bineesh by 7 years and their ages are in the res... Posted in: Mathematics | Date: 07/12/2017 ### Answer: Let age of Kiran and Bineesh be 7 x 7x and 9 x 9x respectively 7 x = 9 x − 7 x = 7 2 = 3.5 7x9x7 x723.5 Kiran's age = 7 x = 7 × 3.5 = 24.5 • ## Question: A rectangular field has to be fenced on three sides leaving a side of 20 fe... Posted in: Mathematics | Date: 08/12/2017 ### Answer: Answer: Option A Explanation: We are given with length and area, so we can find the breadth. as Length * Breadth = Area => 20 * Breadth = 680 => Breadth = 34 feet Area to be fenced = 2B + L = 2*34 + 20 = 88 feet • ## Question: A person walked diagonally across a square plot. Approximately, what was the per... Posted in: Bank PO | Date: 08/12/2017 ### Answer: Answer: Option B Explanation: Consider a square plot as shown above. Let length of each side = 1 1 Then, length of the diagonal = √ 1 2 + 1 2 = √ 2 12122 Distance travelled if walked along the edges = BC + CD = 1 + 1 = 2 112 Distance travelled if walked diagonally = BD = √ 2 = 1.41 21.41 Distance saved = 2 − 1.41 = 0.59 21.410.59 Percent distance saved = 0.59 2 × 100 = 0.59 × 50 ≈ 30 % • ## Question: If the length of a rectangle is halved and its breadth is tripled, what is the p... Posted in: Bank Clerical | Date: 08/12/2017 ### Answer: Answer: D) 50% increase Explanation: Let original length = x and original breadth = y. Original area = xy. New length = x/2 and New breadth=3y New area = Increase in area = New area-original area = Increase % =50 % • ## Question: A towel, when bleached, lost 20% of its length and 10% of its breadth.... Posted in: Bank Clerical | Date: 08/12/2017 ### Answer: Let original length = x and original width = y Decrease in area will be =xy−(80x100×90y100)=(xy−1825xy)=725xyDecrease = (7xy25xy×100)%=28% • ## Question: A rectangular park 60 m long and 40 m wide has two concrete crossroads... Posted in: Bank Clerical | Date: 08/12/2017 ### Answer: Answer: Option C Explanation: Area of the park = (60 x 40) m2 = 2400 m2. Area of the lawn = 2109 m2. Area of the crossroads = (2400 - 2109) m2 = 291 m2. Let the width of the road be x metres. Then, 60x + 40x - x2 = 291 x2 - 100x + 291 = 0 (x - 97)(x - 3) = 0 x = 3. • ## Question: An error 2% in excess is made while measuring the side of a square. What is... Posted in: Mathematics | Date: 08/12/2017 ### Answer: 100 cm is read as 102 cm. A1 = (100 x 100) cm2 and A2 (102 x 102) cm2. (A2 - A1) = [(102)2 - (100)2] = (102 + 100) x (102 - 100) = 404 cm2. Percentage error = 404 x 100 % = 4.04% • ## Question: A circular loop of radius R carrying current I ,lies in X-Y plane with its centr... Posted in: Physics | Date: 08/12/2017 ### Answer: A circular loop behaves like a dipole with one surface North pole and One surface south pole. The lines force emerges from N and will meet at S So net flux through X−YXY plane is zero. • ## Question: The ratio between the length and the breadth of a rectangular park is 3:2. ... Posted in: Bank Clerical | Date: 08/12/2017 ### Answer: Perimeter = Distance covered in 8 min. = 12000 x 8 m = 1600 m. 60 Let length = 3x metres and breadth = 2x metres. Then, 2(3x + 2x) = 1600 or x = 160. Length = 480 m and Breadth = 320 m. Area = (480 x 320) m2 = 153600 m2. • ## Question: On a scale of a map 0.6 cm represents 6.6km. If the distance between two points ... Posted in: Bank Clerical | Date: 11/12/2017 ### Answer: Ans : 885.5 km Solution: .6 cm in map = actual distance of 6.6 km 1 cm in map =6.6/.6 km 80.5 cm in map =80.5x6.6/.6 km = 885.5 km • ## Question: If the price of 357 apples is Rs.1517.25, what will be the approximate price of ... Posted in: Mathematics | Date: 11/12/2017 ### Answer: price of 357 apples = Rs.1517.25price of 1 apple = Rs. 1517.25357price of 49 dozens apples = Rs.(49×12×1517.25357)≈Rs. 2500 • ## Question: A fort had provision of food for 150 men for 45 days. After 10 days, 25 men left... Posted in: Bank Clerical | Date: 11/12/2017 ### Answer: Answer : Option B Explanation : Given that fort had provision of food for 150 men for 45 days Hence, after 10 days, the remaining food is sufficient for 150 men for 35 days Remaining men after 10 days = 150 - 25 = 125 Assume that after 10 days,the remaining food is sufficient for 125 men for x days More men, Less days (Indirect Proportion) ⇒Men150:125}::x:35 ⇒150×35=125x⇒6×35=5x⇒x=6×7=42⇒The remaining food is sufficient for 125 men for 42 days • ## Question: A person works on a project and completes \(\frac{5}{8}$$  of the job ...

Posted in: Mathematics | Date: 11/12/2017

Answer: Work done = 5 8 Balance work = 1 - 5 = 3 8 8 Let the required number of days be x. Then, 5 : 3 = :: 10 : x 5 x x = 3 x 10 8 8 8 8 x = 3 x 10 x 8 8 5 x = 6.

• ## Question: Running at the same constant rate, 6 identical machines can produce a total of 2...

Posted in: Bank Clerical | Date: 11/12/2017

Let the required number of bottles be x. More machines, More bottles (Direct Proportion) More minutes, More bottles (Direct Proportion) Machines 6 : 10 :: 270 : x Time (in minutes) 1 : 4 6 x 1 x x = 10 x 4 x 270 x = (10 x 4 x 270) (6) x = 1800.

• ## Question: A hostel had provisions for 250 men for 40 days. If 50 men left the hostel, how ...

Posted in: Mathematics | Date: 11/12/2017

The hostel had provisions for 250 men for 40 days. This means the total number of meals available were 250 * 40 = 10000. If 50 men left the hostel, the number of men left = 250 - 50 = 200. Now, the number of days food will last = 10000 / 200 = 50. Hence, now the food will last for 50 days.

• ## Question: A garrison of 500 persons had provisions for 27 days. After 3 days a reinforceme...

Posted in: Bank Clerical | Date: 11/12/2017

Total meals available for 500 men= 500*27= 13500. Meals spent= 500*3= 1500. Remaining meals= 13500-1500= 12000. No of days food will last= 12000/800= 15 days.

• ## Question: Ten litre of water per second is lifted from well through 20 m and delivere...

Posted in: Physics | Date: 11/12/2017

Ans:- B 2.5 kW Power = word done in one second Now here motor in one second does work in 2 parts i) Lifting of water 10L water = 10 kg as density of water is 1Kg/L so Work = Change in PE = mgh = 10 * 10 * 20 =2kW ii) Now this water is thrown hence given kinetic energy which is equal to work done by the motor = 0.5 * 10 * 100 =0.5 kW adding the two we get the answer

• ## Question: A garrison had provisions for a certain number of days. After 10 days, $$\f... Posted in: Bank Clerical | Date: 11/12/2017 ### Answer: Assume that initially garrison had provisions for x men for y daysSo, after 10 days, garrison had provisions for x men for (y-10) daysAlso, garrison had provisions for 4x5 men for y days (?x−x5=4x5)More men, Less days (Indirect Proportion)⇒Menx:4x5}::y:(y−10) ⇒x(y−10)=4xy5⇒(y−10)=4y5⇒5(y−10)=4y⇒5y−50=4y⇒y=50 • ## Question: Let a vertical tower AB have its end A on the level ground. Let C be the mid-poi... Posted in: AMIE | Date: 11/12/2017 ### Answer: tan (θ + β) = 1/2 and tan θ = 1/4 1 / 4 + tan β 1 − 1 / 4 tan β = 1 2 14tanβ114tanβ12 9 tanβ = 2 tan β = 2/9 The correct option is B. • ## Question: A box contains 15 green and 10 yellow balls. If 10 balls are randomly drawn, one... Posted in: AMIE | Date: 11/12/2017 ### Answer: p = 15/25 q = 10/25 n = 10 σ2 = npq = 12/5 • ## Question: Twenty meters of wire is available for fencing off a flower-bed in the form of a... Posted in: AIPMT | Date: 11/12/2017 ### Answer: Let M be the angle, the arc of the sector AOB makes with the center O. Let OA = OB = radius r. Given OA + Arc AB + OB = 20 --> 2r + rM = 20 --> M = (20-2r)/r. ..... (1) Area A of the sector = (M/2)rr = 10r-(r*r) ---------- From (1) dA/dr = 10 - 2r = 0 ----> r=5 Second derivative is negative for r =5 We get maximum area at r=5 B = 25 ----------- From (1) • ## Question: A man X has 7 friends, 4 of them are ladies and 3 are men. His wife Y also has 7... Posted in: AIPMT | Date: 11/12/2017 ### Answer: Ans- D 485 • ## Question: 9 engines consume 24 metric tonnes of coal, when each is working 8 hours day. Ho... Posted in: Bank Clerical | Date: 11/12/2017 ### Answer: D. 26 metric tonnes Let required amount of coal be x metric tonnes More engines, more amount of coal (direct proportion) If 3 engines of first type consume 1 unit, then 1 engine will consume 1/3 unit which is its the rate of consumption. If 4 engines of second type consume 1 unit, then 1 engine will consume 1/4 unit which is its the rate of consumption More rate of consumption, more amount of coal (direct proportion) More hours, more amount of coal(direct proportion) Hence we can write as enginesrate of consumptionhours9:813:148:13⎫⎭⎬⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪::24:x ⇒9×13×8×x=8×14×13×24⇒3×8×x=8×6×13⇒3×x=6×13⇒x=2×13=26 • ## Question: In Young’s double slit experiment, slits are separated by 0.5 mm, and... Posted in: AMITE | Date: 12/12/2017 ### Answer: Ans. C-7.8 mm • ## Question: Decomposition of H\(_2$$O$$_2$$follows a first order reaction. In fifty min...

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

Decomposition reaction of H2O2 is: H 2 O 2 ⟶ H 2 O + 1 2 O 2 H2O2H2O12O2 2t½ = 50 mins t½ = 25 mins For first order reaction, t½ = 0.693/k k = 0.693/25 d [ H 2 O 2 ] d t = d [ O 2 ] d t × 2 dH2O2dtdO2dt2 d [ O 2 ] d t = 1 2 × 0.693 25 × 0.05 dO2dt120.693250.05 = 6.93 × 10–4

• ## Question: A garrison had provisions for a certain number of days. After 10 days, $$\f... Posted in: Bank Clerical | Date: 12/12/2017 ### Answer: A- 50 days. Assume that initially garrison had provisions for x men for y daysSo, after 10 days, garrison had provisions for x men for (y-10) daysAlso, garrison had provisions for 4x5 men for y days (?x−x5=4x5)More men, Less days (Indirect Proportion)⇒Menx:4x5}::y:(y−10) ⇒x(y−10)=4xy5⇒(y−10)=4y5⇒5(y−10)=4y⇒5y−50=4y⇒y=50 • ## Question: 9 engines consume 24 metric tonnes of coal, when each is working 8 hours day. Ho... Posted in: Bank Clerical | Date: 12/12/2017 ### Answer: D - 26 metric tonnes. Let required amount of coal be x metric tonnes More engines, more amount of coal (direct proportion) If 3 engines of first type consume 1 unit, then 1 engine will consume 1/3 unit which is its the rate of consumption. If 4 engines of second type consume 1 unit, then 1 engine will consume 1/4 unit which is its the rate of consumption More rate of consumption, more amount of coal (direct proportion) More hours, more amount of coal(direct proportion) Hence we can write as enginesrate of consumptionhours9:813:148:13⎫⎭⎬⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪::24:x ⇒9×13×8×x=8×14×13×24⇒3×8×x=8×6×13⇒3×x=6×13⇒x=2×13=26 • ## Question: 9 examiners can examine a certain number of answer books in 12 days by working 5... Posted in: Bank Clerical | Date: 12/12/2017 ### Answer: Let required number of hours be x More examiners, less hours(indirect proportion) More days, less hours(indirect proportion) More answer books, more hours(direct proportion) Hence we can write as examinersdaysanswer books9:412:302:1⎫⎭⎬⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪::x:5 ⇒9×12×2×5=4×30×1×x⇒x=9×12×2×54×30×1=9×3×2×530=9×2×510=9 • ## Question: The equilibrium constant at 298 K for a reaction A+B⇌C+D is 100. If the i... Posted in: AMITE | Date: 12/12/2017 ### Answer: C- 1.818. Solution : A+B⇌C+DABCD 11111111 1−x1−x1+x1+x1x1x1x1x Kc=[C][D][A][B]KcCDAB =(1+x)2(1−x)21x21x2 =100100 => 1+x1−x1x1x=1010 => 1+x=10−10x1x1010x => 11x=911x9 x=911x911 [D]=1+x=1+911D1x1911 =1.818M • ## Question: 18 g glucose (C\(_6$$H$$_{12}$$O$$_6$$) is added to 178.2 g water. The vapo...

Posted in: AIPMT | Date: 12/12/2017

C-752.4. Molecular mass of water =2×1+1×16=18g2111618g For 178.2g178.2g water nA=9.9nA9.9 Molecular mass of glucose =6×12+12×1+6×16=180g612121616180g For 18g18g glucose nB=0.1nB0.1 XB=0.10.1+9.9)XB0.10.19.9=0.010.01 XA=0.99XA0.99 For lowering of vapour pressure , p=p0AXA=P0A(1−XB)ppA0XAPA01XB P=760(1−0.01)P76010.01 =760−7.67607.6 =752.4torr

• ## Question: The heats of combustion of carbon and carbon monoxide are −393.5 and&...

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

D- -110.5.

• ## Question: At 300 K and 1 atm, 15 mL of a gaseous hydrocarbon requires 375 mL air ...

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

At 300 K and 1 atm, 15 mL of a gaseous hydrocarbon requires 375 mL air containing 20% O22 by volume for complete combustion. After combustion the gases occupy 330 mL. Assuming that the water formed is in liquid form and the volumes were measured at the same temperature and pressure, what is the formula of the hydrocarbon? please get me out of this problem.

• ## Question: In an experiment for determination of refractive index of glass of a prism ...

Posted in: AIPMT | Date: 12/12/2017

A-. 1.5 δ=i+e−AδieA 40=35+79−A403579A 40=114−A40114A A=114−40A11440 =74=r1+r274r1r2 From this we get, μ=1.5μ1.5 δmin

• ## Question: A galvanometer having a coil resistance of 100 Ω gives a full scale d...

Posted in: AMITE | Date: 12/12/2017

A. 0.01 Ω. Galvanometer is a very sensitive instrument therefore it cannot measure heavy currents. In order to convert a Galvanometer into an Ammeter, a very low shunt resistance is connected in parallel to Galvanometer. Value of shunt is so adjusted that most of the current passes through the shunt. If resistance of galvanometer is Rg and it gives full-scale deflection when current Ig is passed through it. Then, V = IgRg V = 1 mA × 100 Ω Let a shunt of resistance (Rs) is connected in parallel to galvanometer. If total current through the circuit is I. I = 10 A = Is + Ig V = IsRs = (I - Ig)Rs (I - Ig)Rs = IgRg (10 - 10-3)Rs = 100 × 10-3 Rs ≈ 0.01 Ω

• ## Question: A pipe open at both ends has a fundamental frequency f in air. The pipe&nbs...

Posted in: AIPMT | Date: 12/12/2017

For open end pipe in air, fundamental frequency: f = V/2L For the pipe closed at one end (dipped in water), fundamental frequency: f' = V/4L' L' = L/2 f' = V/2L = f

• ## Question: A certain number of persons can finish a piece of work in 100 days. If there wer...

Posted in: Bank Clerical | Date: 12/12/2017

C 110. Originally let there be x men. Less men, More days (Indirect Proportion) (x-10) : x :: 100 :110 10x= 1100 x= 110

• ## Question: On a scale of a map 0.6 cm represents 6.6km. If the distance between two points ...

Posted in: Bank Clerical | Date: 12/12/2017

A- 885.5 km. Let the required actual distance be x km More scale distance, More actual distance(direct proportion) Hence we can write as scale distance.6:80.5}::6.6:x ⇒.6x=80.5×6.6⇒.1x=80.5×1.1⇒x=80.5×11=885.5

• ## Question: If the price of 357 apples is Rs.1517.25, what will be the approximate price of ...

Posted in: Mathematics | Date: 12/12/2017

PRICE OF ONE APPLE = 1517.25/357 = 4.25 PRICE OF ONE DOZEN = 4.25 * 12 = 51 Price of 49 Dozens = 51*49 = Rs 2499/-

• ## Question: Half-lives of two radioactive elements A and B are 20 minutes and 40 minute...

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

D-5:4.

• ## Question: An observer looks at a distant tree of height 10 m with a telescope of magn...

Posted in: AIPMT | Date: 12/12/2017

D- 20 times nearer. Telescope creates a focused image of a distant object, so that the object looks nearer. Magnifying power of telescope, M = 20, implies that the tree appears 20 times nearer.

• ## Question: Arrange the following electromagnetic radiations per quantum in the order o...

Posted in: Physics | Date: 12/12/2017

C- C, A, B, D.

• ## Question: An arc lamp requires a direct current of 10 A at 80 V to function. If it is...

Posted in: Physics | Date: 12/12/2017

D- 0.065 H. For the lamp with direct current, V = IR R = 8 Ω XL = Lω = L × (2πf) = L × 100π Z = √ 8 2 + ( L × ( 100 π ) ) 2 Z82L100π2 Z = V r m s I r m s = 220 10 ZVrmsIrms22010 484 = 64 + 104(π2L2) L = 0.065 H

• ## Question: A fort had provision of food for 150 men for 45 days. After 10 days, 25 men left...

Posted in: Bank Clerical | Date: 12/12/2017

B-42. Explanation : Given that fort had provision of food for 150 men for 45 days Hence, after 10 days, the remaining food is sufficient for 150 men for 35 days Remaining men after 10 days = 150 - 25 = 125 Assume that after 10 days,the remaining food is sufficient for 125 men for x days More men, Less days (Indirect Proportion) ⇒Men150:125}::x:35 ⇒150×35=125x⇒6×35=5x⇒x=6×7=42⇒The remaining food is sufficient for 125 men for 42 days

• ## Question: The angle of elevation of the top of a lighthouse 60 m high, from two points on ...

Posted in: Bank Clerical | Date: 13/12/2017

Let BD be the lighthouse and A and C be the two points on ground. Then, BD, the height of the lighthouse = 60 m BAD = 45° , BCD = 60° tan 45 ° = BD BA ⇒ 1 = 60 BA ⇒ BA = 60 m ⋯ ( 1 ) tan45BDBA 160BA BA60 m1 tan 60 ° = BD BC ⇒ √ 3 = 60 BC ⇒ BC = 60 √ 3 = 60 × √ 3 √ 3 × √ 3 = 60 √ 3 3 = 20 √ 3 = 20 × 1.73 = 34.6 m ⋯ ( 2 ) tan60BDBC 360BC BC603603336033 203201.7334.6 m2 Distance between the two points A and C = AC = BA + BC = 60 + 34.6 [∵ Substituted value of BA and BC from (1) and (2)] = 94.6 m

• ## Question: From a tower of 80 m high, the angle of depression of a bus is 30°. How far ...

Posted in: Mathematics | Date: 13/12/2017

Let AC be the tower and B be the position of the bus. Then BC = the distance of the bus from the foot of the tower. Given that height of the tower, AC = 80 m and the angle of depression, DAB = 30° ABC = DAB = 30° (because DA || BC) tan 30 ° = AC BC => tan 30 ° = 80 BC => BC = 80 tan 30 ° = 80 ( 1 √ 3 ) = 80 × 1.73 = 138.4 m tan30ACBC tan3080BC BC = 80tan308013 801.73138.4 m i.e., Distance of the bus from the foot of the tower = 138.4 m

• ## Question: A ladder 10 m long just reaches the top of a wall and makes an angle of 60° ...

Posted in: Mathematics | Date: 13/12/2017

Let BA be the ladder and AC be the wall as shown above. Then the distance of the foot of the ladder from the wall = BC Given that BA = 10 m , BAC = 60° sin 60° = BC BA √ 3 2 = BC 10 BC = 10 × √ 3 2 = 5 × 1.73 = 8.65 m

• ## Question: On the same side of a tower, two objects are located. Observed from the top of t...

Posted in: Mathematics | Date: 13/12/2017

D- 254m. Let DC be the tower and A and B be the objects as shown above. Given that DC = 600 m , DAC = 45°, DBC = 60° tan 60° = DC BC √ 3 = 600 BC BC= 600 √ 3 ⋯ ( 1 ) tan 60°DCBC 3600BC BC= 60031 tan 45° = DC AC 1 = 600 AC AC= 600 ⋯ ( 2 ) tan 45°DCAC 1600AC AC= 6002 Distance between the objects = AB = (AC - BC) = 600 − 600 √ 3 6006003 [∵ from (1) and (2)] = 600 ( 1 − 1 √ 3 ) = 600 ( √ 3 − 1 √ 3 ) = 600 ( √ 3 − 1 √ 3 ) × √ 3 √ 3 = 600 √ 3 ( √ 3 − 1 ) 3 = 200 √ 3 ( √ 3 − 1 ) = 200 ( 3 − √ 3 ) = 200 ( 3 − 1.73 ) = 254 m 600113 600313 60031333 6003313 200331 20033 20031.73 254 m

• ## Question: The angle of elevation of the top of a tower from a certain point is 30°. If...

Posted in: Mathematics | Date: 13/12/2017

Let DC be the tower and A and B be the positions of the observer such that AB = 40 m We have DAC = 30°, DBC = 45° Let DC = h tan 30 ° = DC AC => 1 √ 3 = h AC => AC = h √ 3 ⋯ ( 1 ) tan30DCAC 13hAC AC = h31 tan 45 ° = DC BC => 1 = h BC => BC = h ⋯ ( 2 ) tan45DCBC 1hBC BCh2 We know that, AB = (AC - BC) => 40 = (AC - BC) => 40 = ( h √ 3 − h ) 40h3h[∵ from (1) & (2)] => 40 = h ( √ 3 − 1 ) => h = 40 ( √ 3 − 1 ) = 40 ( √ 3 − 1 ) × ( √ 3 + 1 ) ( √ 3 + 1 ) = 40 ( √ 3 + 1 ) ( 3 − 1 ) = 40 ( √ 3 + 1 ) 2 = 20 ( √ 3 + 1 ) = 20 ( 1.73 + 1 ) = 20 × 2.73 = 54.6 m 40h31 h4031 40313131 403131 40312 2031 201.731202.7354.6 m

• ## Question: The top of a 15 metre high tower makes an angle of elevation of 60° with the...

Posted in: Bank Clerical | Date: 13/12/2017

C-10 m. Given that AC = 15 m, ADB = 30°, AEC = 60° Let DE = h Then, BC = DE = h, AB = (15-h) (∵ AC=15 and BC = h), BD = CE tan 60 ° = AC CE => √ 3 = 15 CE => CE = 15 √ 3 ⋯ ( 1 ) tan60ACCE 315CE CE = 1531 tan 30 ° = AB BD => 1 √ 3 = 15 − h BD tan30ABBD 1315hBD => 1 √ 3 = 15 − h ( 15 √ 3 ) 1315h153(∵ BD = CE and substituted the value of CE from equation 1 ) => ( 15 − h ) = 1 √ 3 × 15 √ 3 = 15 3 = 5 => h = 15 − 5 = 10 m 15h131531535 h15510 m i.e., height of the electric pole = 10 m

• ## Question: A man is watching from the top of a tower a boat speeding away from the tower. T...

Posted in: Bank Clerical | Date: 13/12/2017

Let AB be the tower. Let C and D be the positions of the boat Then, ACB = 45° , ADC = 30°, BC = 100 m tan 45 ° = AB BC => 1 = AB 100 => AB = 100 ⋯ ( 1 ) tan45ABBC 1AB100 AB = 100 1 tan 30 ° = AB BD tan30ABBD => 1 √ 3 = 100 BD 13100BD(∵ Substituted the value of AB from equation 1) => BD = 100 √ 3 1003 CD = (BD - BC) = ( 100 √ 3 − 100 ) = 100 ( √ 3 − 1 ) 100310010031 It is given that the distance CD is covered in 10 seconds. i.e., the distance 100 ( √ 3 − 1 ) 10031 is covered in 10 seconds. Required speed = Distance Time DistanceTime = 100 ( √ 3 − 1 ) 10 = 10 ( 1.73 − 1 ) 1003110101.731 = 7.3 meter/seconds = 7.3 × 18 5 185 km/hr = 26.28 km/hr

• ## Question: A man on the top of a vertical observation tower observes a car moving at a unif...

Posted in: Bank Clerical | Date: 13/12/2017

Let AB be the tower. Let D and C be the positions of the car. Then, ADC = 30° , ACB = 45° Let AB = h, BC = x, CD = y tan 45 ° = AB BC = h x => 1 = h x => h = x ⋯ ( 1 ) tan45ABBChx 1hx hx1 tan 30 ° = AB BD = AB (BC + CD) = h x+y => 1 √ 3 = h x+y => x + y = √ 3 h => y = √ 3 h - x tan30ABBDAB(BC + CD)hx+y 13hx+y x + y = 3h y = 3h - x => y = √ 3 h − h y = 3hh (∵ Substituted the value of x from equation 1 ) => y = h ( √ 3 − 1 ) y = h31 Given that distance y is covered in 8 minutes. i.e, distance h ( √ 3 − 1 ) h31 is covered in 8 minutes. Time to travel distance x = Time to travel distance h (∵ Since x = h as per equation 1). Let distance h is covered in t minutes. since distance is proportional to the time when the speed is constant, we have h ( √ 3 − 1 ) ∝ 8 ⋯ ( A ) h ∝ t ⋯ ( B ) (A) (B) => h ( √ 3 − 1 ) h = 8 t => ( √ 3 − 1 ) = 8 t => t = 8 ( √ 3 − 1 ) = 8 ( 1.73 − 1 ) = 8 .73 = 800 73 minutes = 10 70 73 minutes ≈ 10 minutes 57 seconds

• ## Question: The angle of elevation of a ladder leaning against a wall is 60º and the fo...

Posted in: Mathematics | Date: 13/12/2017

D-24.8 m. PR represents the ladder and RQ represents the wall. cos 60° = PQ PR 1 2 = 12.4 PR PR = 2 × 12.4 = 24.8 m

• ## Question: If all the words, with or without meaning, are written using the letters of the ...

Posted in: AMITE | Date: 13/12/2017

C-46th

• ## Question: In a physical balance working on the principle of moments, when 5 mg weight is p...

Posted in: Physics | Date: 13/12/2017

B-Both the arms are of same length

• ## Question: An observer 2 m tall is 10$$\sqrt{3}$$ m away from a tower. The angle of el...

Posted in: Bank PO | Date: 13/12/2017

B-12m. Basic: tan of angle = opposite side / adjecent side ; tan 30 = 1/ ( square root of 3) = 1 / (1.73) Given man is 2 meter tall so actual height will be 2m addition to obtained opposite side X. Given adjecent side is 10 * (square root of 3) 10 * 1.73 Now tan angle is ===> X / ( 10 * 1.73) = 1 / 1.73 ===> X * 1.73 / 10 * 1.73 = 1 ===> X = 10 m ( obtained opposite side ) therefore Actual height is X + 2 = 10 + 2 = 12 meter.

• ## Question: From a point P on a level ground, the angle of elevation of the top tower is 30&...

Posted in: Bank Clerical | Date: 13/12/2017

A-346m. given height of the tower = 200m angle of elevation = 30deg => tan (30deg) = high of tower/distance from p to foot of the tower => tan (30deg)= 200/d => d= 200/tan (30deg) : tan( 30) = 1/sqrt(3) => d= 346m

• ## Question: A man standing at a point P is watching the top of a tower, which makes an angle...

Posted in: Bank Clerical | Date: 13/12/2017

• ## Question: Two ships are sailing in the sea on the two sides of a lighthouse. The angle of ...

Posted in: Bank Clerical | Date: 13/12/2017

C- 273 m. Let AB be the lighthouse and C and D be the positions of the ships. AB = 100m,∠ACB=30∘, ∠ADB=45∘ AB AC =tan 30∘= 1 √ 3 =>AC=AB∗ √ 3 =100 √ 3 m AB AD =tan 45∘=1 =>AB=AD=100m CD=AC+AD =(100 √ 3 +100) m =100( √ 3 +1) m =100∗2.73 m=273m

• ## Question: Time (T), velocity (C) and angular momentum (h) are chosen as fundamental quanti...

Posted in: Physics | Date: 13/12/2017

A- [M]=[T−11 C−22 h]M∝TXVYhZMTXVYhZ M′L0T0=(T′)X(L1T−1)Y(M1L2T−1)ZML0T0TXL1T1YM1L2T1Z M1L0T0=MZLY+2Z+TX−Y−ZM1L0T0MZLY2ZTXYZ Z=1Z1 Y+2Z=0Y2Z0 Y=−2Y2 X−Y−Z=0XYZ0 X+2−1=0X210 X=1X1 M⟹T−1C−2h1MT1C2h1

• ## Question: If a square and a rhombus stand on the same base, then what is the ratio of the ...

Posted in: Bank PO | Date: 13/12/2017

Ans. Option C - greater than 1 Area of the square is more than that of the rhombus, for having greater height.

• ## Question: The length of a room is 5.5 m and width is 3.75 m. What is the cost of...

Posted in: Bank PO | Date: 13/12/2017

The total cost of paving = Rs. 5.5*3.75*800 = Rs. 16500

• ## Question: “In determining the cost of inventories, it is appropriate to exclude certain ...

Posted in: Accountancy | Date: 13/12/2017

Exclusions from the Cost of Inventories In determining the cost of inventories , it is appropriate to exclude certain costs and recognise them as expenses in the period in which they are incurred. Examples of such costs are: (a) abnormal amounts of wasted materials, labour, or other production costs; (b) storage costs, unless those costs are necessary in the production process prior to a further production stage; (c) administrative overheads that do not contribute to bringing the inventories to their present location and condition; and (d) selling and distribution costs.

• ## Question: What are the issues, with which Accounting Standards deal?

Posted in: Accountancy | Date: 13/12/2017

The mainly issues which deal with Accounting Standard are Recogntion, Measurement/Valuation, Presentation, Disclosure.

• ## Question: When was thinking Indian Congress formed and by whom?

Posted in: History | Date: 13/12/2017

On 28 December 1885, the Indian National Congress was founded at Gokuldas Tejpal Sanskrit College in Bombay, with 72 delegates in attendance.

• ## Question: Which of the following polynomials has the sum of zeroes -3/2 and the product of...

Posted in: Algebra | Date: 13/12/2017

Standard equation for quadratic polynomial : ax2+bx+c =0, can be taken as x2+b/ax+c/a=0 (divided both sides by a). here, sum of zeros = -3/2=-b/a ,which gives b/a=3/2 product of zeros = 1= c/a putting the values of b/a and c/a in general equation, we get; x2+3/2x+1=0 , solving further..we get 2x2+3x+1=0.

• ## Question: Varignon's theorem on moments

Posted in: Statistics | Date: 13/12/2017

The Principle of Moments, also known as Varignon's Theorem, states that the moment of any force is equal to the algebraic sum of the moments of the components of that force. It is a very important principle that is often used in conjunction with the Principle of Transmissibility in order to solve systems of forces that are acting upon and/or within a structure.

• ## Question: A balloon starts rising from the ground with an acceleration of 1.25m/s$$^2$$ . ...

Posted in: Physics | Date: 14/12/2017

a = 1.25m/s^2 Now , v = u + at = 1.25 x 8 = 10 m/s Hence s = 1/2 at^2 = (1.25)(64)/2 = 40 m Now, H= -40m ( due to downward direction.) and 40 = 10t - 5t^2 ( s= ut +1/2 at^2)(placing above obtained and given values) therefore , t^2 - 2t + 8 = 0 **t = 4**

• ## Question: In a cubic closed-packed Structure of mixed oxides, the lattice is made up of ox...

Posted in: Chemistry | Date: 14/12/2017

Actually the bigger molecules like oxygen occupy the lattice points.In ccp unit cell the effective number of atoms occupying lattice points is 8(1/8)+6(1/2)=4 and in ccp the number of tetrahedral voids is 8 so divalents ions will be 8/8 and number of octahedral voids are 4 so one half would be 2 finally,XY2O4.

• ## Question: A ray of light incident on a slab of transparent material is partly reflected fr...

Posted in: Physics | Date: 14/12/2017

A- −11 (i) We know that μ=sinrsinrμsinrsinr and i+r=90∘ir90 or r=90∘−ir90i μ=sinisin(90−i)μsinisin90i =tanitani or i=tan−1(μ)itan1μ =tan−1

• ## Question: In a regular polygon of n sides, each corner is at a distance r from the centre....

Posted in: AMITE | Date: 14/12/2017

Ans:- A If charges were kept at all corners resultant electric field would have been zero So, removal of one charge would result in the same electric field as due to one charge alone. So, E = kQ/r^2

• ## Question: If a party of n persons sit at a round table, then the odds against two specifie...

Posted in: AIPMT | Date: 14/12/2017

B- (n-3) :2. The total number of circular permutations of n people taken all at a time, N = (n - 1)! Let event A = Two specified people sit together. A group of two people, and remaining (n - 2) people can sit on a round table in [{1 + (n - 2)} - 1]! i.e. (n - 2)! ways. The two specified people can interchange their places in 2! ways. Hence favourable ways, N(A) = (n - 2)! 2! P(A)PA = (n−2)!2!(n−1)!n22n1 = 2n−12n1 P(A¯¯¯¯)PA = 1−2n−112n1 = n−3n−1n3n1 Therefore the odds against two specified people sitting next to each other are P(A¯¯¯¯)PA to P(A)PA i.e. (n−3):2

• ## Question: In a class tournament, all participants were to play different games with one an...

Posted in: AIPMT | Date: 14/12/2017

B-15. Let the no. of participants be nn. If no participant fell ill, then the no. of games played = nC2nC2 Each player will play n−1n1 games in the tournament. These n-1 games include 1 game which both the player played with each other. This one game is counted with both the players. The two participants played 3 games each and fell ill. ∴ The no. of games played = nC2−[(n−1)+(n−1)−1]+6=84nC2n1n11684 (given) ⇒n(n−1)2nn12−2n+9=84 ⇒n2−5n−150=0 ⇒n=15or−10(notpossible) ⇒n=15

• ## Question: A vertical pole PO is standing at the centre O of a square ABCD. If AC subtends ...

Posted in: AMIE | Date: 14/12/2017

C-60°.

Posted in: AIPMT | Date: 14/12/2017

C. Malonic acid

• ## Question: The headlight of a train of length 200m is switched on when it starts from rest ...

Posted in: Chemistry | Date: 14/12/2017

Ans:- A. after 20s the the distance covered by the train is s = 1/2( a t^2) s = 1/2 *1/2 *20*20 s = 100 m the velocity of the train after 20s is v2 = u2 +2as (u = 0 , since starting from rest ) v2 = 2*0.5*100 v =10 m/s so after 20 secs the head light of train covers 100 m distance and then the back light is switched on,in order to see both the actions in same time the observer should cover the 300 m distance in 20 secs relative to train and in opposite direction. V of observer with respect to train should be = 300/20 = - 15 m/s (- sign for opposite direction) - 15 = Vframe - Vtrain - 15 = Vframe - 10 Vframe = - 5 m/s Hence The correct answer is 5 m/s in the opposite direction. (A)

• ## Question: A body starts from rest with uniform acceleration. Its velocity after the 2n sec...

Posted in: AMIE | Date: 14/12/2017

Given that the velocity at the 2n second interval = v0 = a x 2n. This gives a = v0/2n Displacement after n seconds is 0.5 a nxn Displacement after 2n seconds = 0.5 a . (2n) x (2n) Subtracting, the displacement in the last second is 0.5 x a x (3n^2) Replacing the value of a, we get the distance covered in last n second = 0.5 x v0 / 2n x 3 n^2 = (3/4) x v0 x n

• ## Question: The minimum kinetic energy needed to project a body of mass m from the earth'...

Posted in: Chemistry | Date: 14/12/2017

C- mgR. K.E. = ½ mv2e ­where ve = escape velocity = v2gR ? K.E = ½ m x 2gR = mgR 3

• ## Question: Two spherical vessels of equal volume are connected by 'a narrow tube. The a...

Posted in: Chemistry | Date: 14/12/2017

C- 4/3 atm

• ## Question: A planet is observed by an astronomical refracting telescope having an objective...

Posted in: AIPMT | Date: 14/12/2017

A- The distance between the objective and the eyepiece is 16.02 m

• ## Question: An aeroplane when 900 m high passes vertically above another aeroplane at an ins...

Posted in: Bank Clerical | Date: 15/12/2017

Answer: Option A 381 m Explanation: Let C and D be the position of the aeroplanes. Given that CB = 900 m, CAB = 60°, DAB = 45° From the right ABC, tan 60 ° = CB AB √ 3 = 900 AB AB = 900 √ 3 = 900 × √ 3 √ 3 × √ 3 = 900 √ 3 3 = 300 √ 3 tan60CBAB 3900AB AB9003 900333900333003 From the right ABD, tan 45 ° = DB AB 1 = DB AB DB = AB = 300 √ 3 tan45DBAB 1DBAB DBAB3003 Required height = CD = (CB-DB) = ( 900 − 300 √ 3 ) = ( 900 − 300 × 1.73 ) = ( 900 − 519 ) = 381 m

• ## Question: A vertical pole fixed to the ground is divided in the ratio 1:9 by a mark on it ...

Posted in: Mathematics | Date: 15/12/2017

Let CB be the pole and point D divides it such that BD : DC = 1 : 9 Given that AB = 15 m Let the the two parts subtend equal angles at point A such that CAD = BAD = θ From "Angle Bisector Theorem", we have BD DC = AB AC BDDCABAC ⇒ 1 9 = 15 AC 1915AC [∵ BD : DC = 1 : 9 and AB = 15(given)] => AC = 15 × 9 m ...(eq: 1) From the right ABC, CB = √ AC 2 − AB 2 CBAC2AB2(∵ Pythagorean theorem) = √ ( 15 × 9 ) 2 − 15 2 1592152(∵AC=15×9(eq:1) and AB=15 m(given)] = √ 15 2 × 9 2 − 15 2 = √ 15 2 ( 9 2 − 1 ) = √ 15 2 × 80 = √ 15 2 × 16 × 5 = 15 × 4 × √ 5 = 60 √ 5 m

• ## Question: From the foot and the top of a building of height 230 m, a person observes the t...

Posted in: Bank Clerical | Date: 15/12/2017

Let ED be the building and AC be the tower. Given that ED = 230 m, ADC = b, AEB = a Also given that tan a = 5/12 and tan b = 4/5 Let AC = h Required Distance = Distance between the top of these buildings = AE From the right ABE, tan ( a ) = AB BE tan(aABBE => 5 12 = (h-230) BE 512(h-230)BE [∵ tan(a)=5/12(given), AB = (AC-BC) = (AC-ED) = (h-230)] => BE = 12 (h-230) 5 ⋯ ( e q : 1 ) 12(h-230)5eq1 From the right ACD, tan ( b ) = AC CD tan(bACCD => 4 5 = h CD 45hCD [∵ tan(b) = 4/5(given), AC=h] => CD = 5 h 4 ⋯ ( e q : 2 ) 5h4eq2 From the diagram, BE = CD ⇒ 12 (h-230) 5 = 5 h 4 12(h-230)55h4 (from eq:1 & eq:2) ⇒ 48 h − ( 4 × 12 × 230 ) = 25 h ⇒ 23 h = ( 4 × 12 × 230 ) 48h41223025h 23h412230 ⇒ h = ( 4 × 12 × 230 ) 23 = 480 m h41223023480 m ⋯ ( e q : 3 ) eq3 AB = (AC - BC) = (480 - 230) [∵ Since AC=h=480(from eq:3) and BC=ED=230 m(given)] = 250 m In the triangle ABE, tan(a) = 5/12. Let's figure out the value of sin(a) now. Consider a triangle with opposite side = 5 and adjacent side = 12 such that tan(a) = 5/12 hypotenuse = √ 5 2 + 12 2 = 13 5212213 i.e., sin(a) = opposite side hypotenuse = 5 13 opposite sidehypotenuse513 We have seen that sin(a) = 5 13 513 ⇒ AB AE = 5 13 ⇒ AE = AB × 13 5 = 250 × 13 5 = 650 m ABAE513 AE = AB135 250135650 m i.e., Distance between the top of the buildings = 650 m

• ## Question: A person, standing exactly midway between two towers, observes the top of the tw...

Posted in: Bank Clerical | Date: 15/12/2017

Let ED be the taller tower and AB be the shorter tower. Let C be the point of observation. Given that ACB = 22.5° and DCE = 67.5° Given that C is the midpoint of BD. Hence, BC = CD From the right ABC, tan 22.5 ° = AB BC ⋯ ( e q : 1 ) tan22.5ABBCeq1 From the right CDE, tan 67.5 ° = ED CD ⋯ ( e q : 2 ) tan67.5EDCDeq2 ( e q : 2 ) ( e q : 1 ) ⇒ tan 67.5 ° tan 22.5 ° = ( ED CD ) ( AB BC ) eq2eq1tan67.5tan22.5EDCDABBC = ED AB EDAB(∵ CD=BC) ⇒ tan ( 90 ° − 22.5 ° ) tan 22.5 ° = ED AB tan9022.5tan22.5EDAB ⇒ cot 22.5 ° tan 22.5 ° = ED AB cot22.5tan22.5EDAB [∵ tan(90-θ)=cot θ] ⇒ ( 1 tan 22.5 ° ) tan 22.5 ° = ED AB 1tan22.5tan22.5EDAB [ ∵ cot θ = 1 tan θ ] cotθ1tanθ ⇒ ED AB = 1 ( tan 22.5 ° ) 2 = 1 ( √ 2 − 1 ) 2 = ( 1 √ 2 − 1 ) 2 = [ ( √ 2 + 1 ) ( √ 2 − 1 ) ( √ 2 + 1 ) ] 2 = [ ( √ 2 + 1 ) ( 2 − 1 ) ] 2 = [ ( √ 2 + 1 ) 1 ] 2 = ( √ 2 + 1 ) 2 = ( 2 + 2 √ 2 + 1 ) = ( 3 + 2 √ 2 ) EDAB1tan22.52 12121212 2121212 212122112 2122221 322 Required ratio = ED : AB = ( 3 + 2 √ 2 ) : 1 3221

• ## Question: The angle of elevation of the top of the tower from a point on the ground is&nbs...

Posted in: Bank PO | Date: 15/12/2017

D-15 m. Let P be the point of observation and QR be the tower. Given that θ = sin − 1 ( 3 5 ) θsin135 and PQ = 20 m Let the height of the tower, QR = h and PR = x From the right PQR, sin θ = QR PR ⇒ sin [ sin − 1 ( 3 5 ) ] = h x ⇒ 3 5 = h x ⇒ x = 5 h 3 ⋯ ( e q : 1 ) sinθQRPR sinsin135hx 35hx x5h3eq1 From Pythagorean theorem, we have PQ 2 + QR 2 = PR 2 20 2 + h 2 = x 2 PQ2QR2PR2 202h2x2 20 2 + h 2 = ( 5 h 3 ) 2 202h25h32(∵ Substituted the value of x from eq:1) 20 2 + h 2 = 25 h 2 9 16 h 2 9 = 20 2 4 h 3 = 20 h = 3 × 20 4 = 15 m 202h225h29 16h29202 4h320 h320415 m i.e., height of the tower = 15 m

Posted in: Mathematics | Date: 15/12/2017

Let RQ be the pole and PQ be the shadow Given that RQ = 18 m and PQ = 6 √ 3 63 m Let the angle of elevation, RPQ = θ From the right PQR, tan θ = RQ PQ = 18 6 √ 3 = 3 √ 3 = √ 3 tanθRQPQ1863333 ⇒ θ = tan − 1 ( √ 3 ) = 60°

• ## Question: Two persons are on either sides of a tower of height 50 m. The persons observers...

Posted in: Bank Clerical | Date: 15/12/2017

Let BD be the tower and A and C be the positions of the persons. Given that BD = 50 m, BAD = 30°, BCD = 60° From the right ABD, tan 30° = BD BA ⇒ 1 √ 3 = 50 BA ⇒ BA = 50 √ 3 tan 30° = BDBA 1350BA BA503 From the right CBD, tan 60° = BD BC ⇒ √ 3 = 50 BC ⇒ BC = 50 √ 3 = 50 × √ 3 √ 3 × √ 3 = 50 √ 3 3 tan 60° = BDBC 350BC BC503503335033 Distance between the two persons = AC = BA + BC = 50 √ 3 + 50 √ 3 3 = √ 3 ( 50 + 50 3 ) = 200 √ 3 3 m 5035033 350503 20033 m i.e., the distance travelled by the car in 10 seconds = 200 √ 3 3 20033 m Speed of the car = Distance Time DistanceTime = ( 200 √ 3 3 ) 10 = 20 √ 3 3 meter/second = 20 √ 3 3 × 18 5 km/hr = 24 √ 3 km/hr

• ## Question: A uniform chain of length L and mass M is lying on a smooth table and one-third ...

Posted in: Physics | Date: 15/12/2017

D- MgL/18. unit length of rope is M/L given L/3 part of rope is hanging we have to solve using integration methods, lets say 'x' part of rope is consided with an element 'dx' which is pulled up with limits from 0 to L/3 Potential energy = mgh here dE= integral of ( Mx/L*g*dx) E = integral of ( M/L*g*x.dx) limits from 0 to L/3 P.E = MgL/18

• ## Question: he elevation of the summit of a mountain from its foot is 45°. After ascendi...

Posted in: Bank Clerical | Date: 15/12/2017

Let A be the foot and C be the summit of a mountain. Given that CAB = 45° From the diagram, CB is the height of the mountain. Let CB = x Let D be the point after ascending 2 km towards the mountain such that AD = 2 km and given that DAY = 30° It is also given that from the point D, the elevation is 60° i.e., CDE = 60° From the right ABC, tan 45 ° = CB AB tan45CBAB => 1 = x AB 1xAB [∵ CB = x(the height of the mountain)] => AB = x ... (eq:1) From the right AYD, sin 30 ° = DY AD sin30DYAD => 1 2 = DY 2 12DY2 (∵ Given that AD = 2) => DY = 1 ... (eq:2) cos 30 ° = AY AD cos30AYAD => √ 3 2 = AY 2 32AY2(∵ Given that AD = 2) => AY = √ 3 3 ... (eq:3) From the right CED, tan 60 ° = CE DE tan60CEDE ⇒ tan 60 ° = (CB - EB) YB tan60(CB - EB)YB[∵ CE=(CB-EB) and DE=YB)] ⇒ tan 60 ° = (CB - DY) (AB - AY) tan60(CB - DY)(AB - AY)[∵ EB=DY and YB=(AB-AY)] ⇒ tan 60 ° = (x - 1) ( x − √ 3 ) tan60(x - 1)x3 [∵ CB=x, DY=1(eq:2), AB=x(eq:1) and AY = √ 3 3(eq:3)] ⇒ √ 3 = (x - 1) ( x − √ 3 ) ⇒ x √ 3 − 3 = x − 1 ⇒ x ( √ 3 − 1 ) = 2 ⇒ 0.73 x = 2 ⇒ x = 2 0.73 = 2.7 3(x - 1)x3 x33x1 x312 0.73x2 x20.732.7 i.e., the height of the mountain = 2.7 km

• ## Question: Two coherent sources of different intensities send waves which interfere. The ra...

Posted in: Physics | Date: 15/12/2017

C-9:4.

• ## Question: The relative density of a metal may be found by hanging a block of the metal fro...

Posted in: Physics | Date: 15/12/2017

B- 5.00 ± 11%. Weight in air =(5.00±0.05)N Weight in water=(4.00±0.05)N Loss of weight in water =(1.00±0.1)N Now relative density =weightinair weight loss in water i.e. R . D=5.00±0.051.00±0.1 Now relative density with max permissible error =5.001.00±(0.055.00+0.11.00)×100=5.0±(1+10) =5.0±11

• ## Question: To a man standing outside his house, the angles of elevation of the top and bott...

Posted in: Bank Clerical | Date: 15/12/2017

D-3.65 m. Let AB be the man and CD be the window Given that the height of the man, AB = 180 cm, the distance between the man and the wall, BE = 5 m, DAF = 45° , CAF = 60° From the diagram, AF = BE = 5 m From the right AFD, tan 45 ° = DF AF 1 = DF 5 DF = 5 ⋯ ( 1 ) tan45DFAF 1DF5 DF = 51 From the right AFC, tan 60 ° = CF AF √ 3 = CF 5 CF = 5 √ 3 ⋯ ( 2 ) tan60CFAF 3CF5 CF532 Length of the window = CD = (CF - DF) = 5 √ 3 − 5 535[∵ Substituted the value of CF and DF from (1) and (2)] = 5 ( √ 3 − 1 ) = 5 ( 1.73 − 1 ) = 5 × 0.73 = 3.65 m

• ## Question: A five-digit numbers divisible by 3 is to be formed using the numerals 0, 1, 2, ...

Posted in: AMIE | Date: 15/12/2017

A-216. We have two set of numbers: 1, 2, 3, 4, 5 and 0, 1, 2, 4, 5. How many 5 digit numbers can be formed using these two sets: 1, 2, 3, 4, 5 --> 5! as any combination of these digits would give us 5 digit number divisible by 3. 5!=120. 0, 1, 2, 4, 5 --> here we can not use 0 as the first digit, otherwise number won't be any more 5 digit and become 4 digit. So, desired # would be total combinations 5!, minus combinations with 0 as the first digit (combination of 4) 4! --> 5!-4!=4!(5-1)=4!*4=96 120+96=216

• ## Question: Two vertical poles are 200 m apart and the height of one is double that of the o...

Posted in: Mathematics | Date: 15/12/2017

Let AB and CD be the poles with heights h and 2h respectively. Given that distance between the poles, BD = 200 m Let E be the middle point of BD, AEB = θ CED = (90-θ) (∵ given that angular elevations are complementary) Since E is the middle point of BD, we have BE = ED = 100 m From the right ABE, tan θ = AB BE tan θ = h 100 h = 100 tan θ ⋯ ( 1 ) tanθABBE tanθh100 h = 100tanθ1 From the right EDC, tan ( 90 − θ ) = CD ED cot θ = 2h 100 [ ∵ tan ( 90 − θ ) = cot θ ] 2h = 100 cot θ ⋯ ( 2 ) tan90θCDED cotθ2h100tan90θcotθ 2h 100cotθ2 ( 1 ) × ( 2 ) => 2 h 2 = 100 2 122h21002 [ ∵ tan θ × cot θ = tan θ × 1 tan θ = 1 ] tanθcotθtanθ1tanθ1 => √ 2 h = 100 2h100 => h = 100 √ 2 = 100 × √ 2 √ 2 × √ 2 = 50 √ 2 = 50 × 1.41 = 70.5 h1002100222 502501.4170.5 => 2h = 2 × 70.5 = 141 2h270.5141 i.e., the height of the poles are 70.5 m and 141 m.

• ## Question: The angles of depression and elevation of the top of a wall 11 m high from top a...

Posted in: Mathematics | Date: 15/12/2017

Let DC be the wall, AB be the tree. Given that DBC = 30°, DAE = 60°, DC = 11 m tan 30° = DC BC 1 √ 3 = 11 BC BC = 11 √ 3 m AE = BC = 11 √ 3 m ⋯ ( 1 ) tan 30°DCBC 1311BC BC = 113 m AE = BC =113 m1 tan 60 ° = ED AE tan60EDAE √ 3 = ED 11 √ 3 3ED113 [∵ Substituted value of AE from (1)] ED = 11 √ 3 × √ 3 = 11 × 3 = 33 113311333 Height of the tree = AB = EC = (ED + DC) = (33 + 11) = 44 m

• ## Question: The streets of a city are arranged like the lines of a chess board. There are &l...

Posted in: AIPMT | Date: 15/12/2017

it can be arranged as a chessboard with m-1 steps up down and n-1 steps left right. shortest possible distance will be m-1 steps down and n-1 steps right. no. of ways is….(m+n-2)! / (m-1)!(n-1)!

• ## Question: The displacement y of a particle executing a certain periodic motion is given by...

Posted in: Physics | Date: 15/12/2017

B-3. y = 4 cos2 (1/2 t) sin (1000 t) = 2 x 2 cos2(t/2)sin (1000 t) = 2 x (1 + cos t) sin (1000 t) = 2 sin (1000 t) + 2 cos t sin (1000 t) = 2 sin (1000 t) + sin [(1000+1)t] +sin [(1000−1)t] = 2 sin (1000 t) + sin (1001)t +sin (999)t = y1 + y2 + y3 As the above expression involves three different waves the displacement given is a result of superposition of three different waves.

• ## Question: A balloon leaves the earth at a point A and rises vertically at uniform speed. A...

Posted in: Bank Clerical | Date: 15/12/2017

Let C be the position of John. Let A be the position at which balloon leaves the earth and B be the position of the balloon after 2 minutes. Given that CA = 150 m, BCA = 60° tan 60 ° = BA CA √ 3 = B A 150 BA = 150 √ 3 tan60BACA 3BA150 BA1503 i.e, the distance travelled by the balloon = 150 √ 3 1503 meters time taken = 2 min = 2 × 60 = 120 seconds Speed = Distance Time DistanceTime = 150 √ 3 120 = 1.25 √ 3 = 1.25 × 1.73 = 2.16 meter/second

• ## Question: A vertical tower stands on ground and is surmounted by a vertical flagpole of he...

Posted in: Bank Clerical | Date: 15/12/2017

A-9 m. Let DC be the vertical tower and AD be the vertical flagpole. Let B be the point of observation. Given that AD = 18 m, ABC = 60°, DBC = 30° Let DC be h. tan 30 ° = DC BC 1 √ 3 = h BC h = BC √ 3 ⋯ ( 1 ) tan30DCBC 13hBC hBC31 tan 60 ° = AC BC √ 3 = 18 + h BC 18+h = BC × √ 3 ⋯ ( 2 ) tan60ACBC 318hBC 18+hBC32 ( 1 ) ( 2 ) => h 18 + h = ( BC √ 3 ) ( BC × √ 3 ) = 1 3 => 3 h = 18 + h => 2 h = 18 => h = 9 m 12h18hBC3BC313 3h18h 2h18 h9 m i.e., the height of the tower = 9 m

• ## Question: From the top of a hill 100 m high, the angles of depression of the top and botto...

Posted in: Bank Clerical | Date: 15/12/2017

Answer: Option C Explanation: Consider the diagram shown above. AC represents the hill and DE represents the pole Given that AC = 100 m XAD = ADB = 30° (∵ AX || BD ) XAE = AEC = 60° (∵ AX || CE) Let DE = h Then, BC = DE = h, AB = (100-h) (∵ AC=100 and BC = h), BD = CE tan 60 ° = AC CE => √ 3 = 100 CE => CE = 100 √ 3 ⋯ ( 1 ) tan60ACCE 3100CE CE = 10031 tan 30 ° = AB BD => 1 √ 3 = 100 − h BD tan30ABBD 13100hBD => 1 √ 3 = 100 − h ( 100 √ 3 ) 13100h1003(∵ BD = CE and substituted the value of CE from equation 1) => ( 100 − h ) = 1 √ 3 × 100 √ 3 = 100 3 = 33.33 => h = 100 − 33.33 = 66.67 m 100h131003 100333.33 h10033.3366.67 m i.e., the height of the pole = 66.67 m

• ## Question: The angle of elevation of the top of a lighthouse 60 m high, from two points on ...

Posted in: Mathematics | Date: 15/12/2017

Let BD be the lighthouse and A and C be the two points on ground. Then, BD, the height of the lighthouse = 60 m BAD = 45° , BCD = 60° tan 45 ° = BD BA ⇒ 1 = 60 BA ⇒ BA = 60 m ⋯ ( 1 ) tan45BDBA 160BA BA60 m1 tan 60 ° = BD BC ⇒ √ 3 = 60 BC ⇒ BC = 60 √ 3 = 60 × √ 3 √ 3 × √ 3 = 60 √ 3 3 = 20 √ 3 = 20 × 1.73 = 34.6 m ⋯ ( 2 ) tan60BDBC 360BC BC603603336033 203201.7334.6 m2 Distance between the two points A and C = AC = BA + BC = 60 + 34.6 [∵ Substituted value of BA and BC from (1) and (2)] = 94.6 m

• ## Question: From a tower of 80 m high, the angle of depression of a bus is 30°. How far ...

Posted in: Mathematics | Date: 15/12/2017

Let AC be the tower and B be the position of the bus. Then BC = the distance of the bus from the foot of the tower. Given that height of the tower, AC = 80 m and the angle of depression, DAB = 30° ABC = DAB = 30° (because DA || BC) tan 30 ° = AC BC => tan 30 ° = 80 BC => BC = 80 tan 30 ° = 80 ( 1 √ 3 ) = 80 × 1.73 = 138.4 m tan30ACBC tan3080BC BC = 80tan308013 801.73138.4 m i.e., Distance of the bus from the foot of the tower = 138.4 m

• ## Question: A ladder 10 m long just reaches the top of a wall and makes an angle of 60° ...

Posted in: Bank Clerical | Date: 15/12/2017

Let BA be the ladder and AC be the wall as shown above. Then the distance of the foot of the ladder from the wall = BC Given that BA = 10 m , BAC = 60° sin 60° = BC BA √ 3 2 = BC 10 BC = 10 × √ 3 2 = 5 × 1.73 = 8.65 m

• ## Question: A uniform rod of mass m and length l makes a constant angle θ with an axis...

Posted in: AMITE | Date: 15/12/2017

Man per unit length =MlMl Consider an element of width dx at a distance x from 0 mass of element =dm=M2dmM2dxdx M.I= man × perpendicular distance from axis of rotation Hence Ml2sinθ12Ml2sinθ12 is a correct answer.

• ## Question: A simple pendulum has a string of length l and bob of mass m. When the bob is at...

Posted in: AMIE | Date: 15/12/2017

D-6mg. This question solve by method of conservation of energy. at the highest position tension in string is zero .now we proceed mg=mv^2/l at tje highest position v^2=gl now at the lowest position apply conservation of energy 1/2mv^2+mg.2l=1/2mv'^2 v'2=5gl where v'is velocity of bob at lowest position now, T=6mg

• ## Question: A ball is projected upwards from the foot of a tower. The ball crosses the top o...

Posted in: AMIE | Date: 15/12/2017

Time taken to go uptoU and then come back to the ground required 12 sec. So 6 s up then 6 s in coming down. the time taken between climbing from T to U and then coming to T again(crossing T twice) =6 s so time taken to go upto T from the ground=(12-6)/2=3s now if we consider the journey from ground to U: 0=u-6x10 ....... putting in 1st eq. u=60 m/s now tower height:H= H=60x3-1/2 x10x3x3.....putting in second eq H=135 m

• ## Question: A wire has a mass (0.3 ± 0.003)g, radius (0.5 ± 0.005)mm and lengt...

Posted in: Physics | Date: 15/12/2017

D-4. Since density is mass÷volume, For a cylinder it becomes- mass÷(pi×radius^2×length) Relative percent errors for- Mass-0.003÷0.3×100=1% Radius^2-2×0.005÷0.5×100=2% Length-0.06÷0.6×100=1% THE UNITS CANCEL THEMSELVES FROM THE NUMERATOR AND DENOMINATOR. therefore, maximum percentage error in density-1%+2%+1%=4% so, the answer is 4%

• ## Question: A very broad elevator is going up vertically with a constant acceleration of 2m/...

Posted in: AIPMT | Date: 15/12/2017

Component of velocity of ball relative to lift are ux=4cos30∘=23–√m/sux4cos3023ms uy=4sin30∘=2m/suy4sin302ms and acceleration of ball relative to lift is a=10+2=12m/s2a10212ms2 in negative y direction acting downwards. Therefore Time of flight T=2uyaT2uya =2×2122212 =1/3s

• ## Question: On the same side of a tower, two objects are located. Observed from the top of t...

Posted in: Bank Clerical | Date: 15/12/2017

Answer: Option D Explanation: Let DC be the tower and A and B be the objects as shown above. Given that DC = 600 m , DAC = 45°, DBC = 60° tan 60° = DC BC √ 3 = 600 BC BC= 600 √ 3 ⋯ ( 1 ) tan 60°DCBC 3600BC BC= 60031 tan 45° = DC AC 1 = 600 AC AC= 600 ⋯ ( 2 ) tan 45°DCAC 1600AC AC= 6002 Distance between the objects = AB = (AC - BC) = 600 − 600 √ 3 6006003 [∵ from (1) and (2)] = 600 ( 1 − 1 √ 3 ) = 600 ( √ 3 − 1 √ 3 ) = 600 ( √ 3 − 1 √ 3 ) × √ 3 √ 3 = 600 √ 3 ( √ 3 − 1 ) 3 = 200 √ 3 ( √ 3 − 1 ) = 200 ( 3 − √ 3 ) = 200 ( 3 − 1.73 ) = 254 m

• ## Question: The angle of elevation of the top of a tower from a certain point is 30°. If...

Posted in: Mathematics | Date: 15/12/2017

Let DC be the tower and A and B be the positions of the observer such that AB = 40 m We have DAC = 30°, DBC = 45° Let DC = h tan 30 ° = DC AC => 1 √ 3 = h AC => AC = h √ 3 ⋯ ( 1 ) tan30DCAC 13hAC AC = h31 tan 45 ° = DC BC => 1 = h BC => BC = h ⋯ ( 2 ) tan45DCBC 1hBC BCh2 We know that, AB = (AC - BC) => 40 = (AC - BC) => 40 = ( h √ 3 − h ) 40h3h[∵ from (1) & (2)] => 40 = h ( √ 3 − 1 ) => h = 40 ( √ 3 − 1 ) = 40 ( √ 3 − 1 ) × ( √ 3 + 1 ) ( √ 3 + 1 ) = 40 ( √ 3 + 1 ) ( 3 − 1 ) = 40 ( √ 3 + 1 ) 2 = 20 ( √ 3 + 1 ) = 20 ( 1.73 + 1 ) = 20 × 2.73 = 54.6 m

• ## Question: The top of a 15 metre high tower makes an angle of elevation of 60° with the...

Posted in: Mathematics | Date: 15/12/2017

Consider the diagram shown above. AC represents the tower and DE represents the pole. Given that AC = 15 m, ADB = 30°, AEC = 60° Let DE = h Then, BC = DE = h, AB = (15-h) (∵ AC=15 and BC = h), BD = CE tan 60 ° = AC CE => √ 3 = 15 CE => CE = 15 √ 3 ⋯ ( 1 ) tan60ACCE 315CE CE = 1531 tan 30 ° = AB BD => 1 √ 3 = 15 − h BD tan30ABBD 1315hBD => 1 √ 3 = 15 − h ( 15 √ 3 ) 1315h153(∵ BD = CE and substituted the value of CE from equation 1 ) => ( 15 − h ) = 1 √ 3 × 15 √ 3 = 15 3 = 5 => h = 15 − 5 = 10 m 15h131531535 h15510 m i.e., height of the electric pole = 10 m

• ## Question: A man is watching from the top of a tower a boat speeding away from the tower. T...

Posted in: Bank Clerical | Date: 15/12/2017

Answer: Option A Explanation: Consider the diagram shown above. Let AB be the tower. Let C and D be the positions of the boat Then, ACB = 45° , ADC = 30°, BC = 100 m tan 45 ° = AB BC => 1 = AB 100 => AB = 100 ⋯ ( 1 ) tan45ABBC 1AB100 AB = 100 1 tan 30 ° = AB BD tan30ABBD => 1 √ 3 = 100 BD 13100BD(∵ Substituted the value of AB from equation 1) => BD = 100 √ 3 1003 CD = (BD - BC) = ( 100 √ 3 − 100 ) = 100 ( √ 3 − 1 ) 100310010031 It is given that the distance CD is covered in 10 seconds. i.e., the distance 100 ( √ 3 − 1 ) 10031 is covered in 10 seconds. Required speed = Distance Time DistanceTime = 100 ( √ 3 − 1 ) 10 = 10 ( 1.73 − 1 ) 1003110101.731 = 7.3 meter/seconds = 7.3 × 18 5 185 km/hr = 26.28 km/hr

• ## Question: A man on the top of a vertical observation tower observes a car moving at a unif...

Posted in: Bank Clerical | Date: 15/12/2017

Answer: Option B Explanation: Consider the diagram shown above. Let AB be the tower. Let D and C be the positions of the car. Then, ADC = 30° , ACB = 45° Let AB = h, BC = x, CD = y tan 45 ° = AB BC = h x => 1 = h x => h = x ⋯ ( 1 ) tan45ABBChx 1hx hx1 tan 30 ° = AB BD = AB (BC + CD) = h x+y => 1 √ 3 = h x+y => x + y = √ 3 h => y = √ 3 h - x tan30ABBDAB(BC + CD)hx+y 13hx+y x + y = 3h y = 3h - x => y = √ 3 h − h y = 3hh (∵ Substituted the value of x from equation 1 ) => y = h ( √ 3 − 1 ) y = h31 Given that distance y is covered in 8 minutes. i.e, distance h ( √ 3 − 1 ) h31 is covered in 8 minutes. Time to travel distance x = Time to travel distance h (∵ Since x = h as per equation 1). Let distance h is covered in t minutes. since distance is proportional to the time when the speed is constant, we have h ( √ 3 − 1 ) ∝ 8 ⋯ ( A ) h ∝ t ⋯ ( B ) (A) (B) => h ( √ 3 − 1 ) h = 8 t => ( √ 3 − 1 ) = 8 t => t = 8 ( √ 3 − 1 ) = 8 ( 1.73 − 1 ) = 8 .73 = 800 73 minutes = 10 70 73 minutes ≈ 10 minutes 57 seconds

• ## Question: The angle of elevation of a ladder leaning against a wall is 60º and the fo...

Posted in: Bank Clerical | Date: 16/12/2017

D-24.8 m. Angle = 60º and distance between wall and ladder= 12.4 m. Length of ladder= 2 x distance between wall and ladder = (2 x 12.4) m = 24.8 m.

• ## Question: What is Trade Union?

Posted in: Commerce Subjects | Date: 16/12/2017

An organization whose membership consists of workers and union leaders, united to protect and promote their common interests. The principal purposes of a labor union are to (1) negotiate wages and working condition terms, (2) regulate relations between workers (its members) and the employer, (3) take collective action to enforce the terms of collective bargaining, (4) raise new demands on behalf of its members, and (5) help settle their grievances. A trade union may be: (a) A company union that represents interests of only one company and may not have any connection with other unions.

Posted in: NEST | Date: 16/12/2017

C- pineal gland secretes melatonin in animals and this hormone regulates sleep.

• ## Question: In a cubic closed packed Structure of mixed oxides, the lattice is made up of ox...

Posted in: Chemistry | Date: 16/12/2017

Actually the bigger molecules like oxygen occupy the lattice points.In ccp unit cell the effective number of atoms occupying lattice points is 8(1/8)+6(1/2)=4 and in ccp the number of tetrahedral voids is 8 so divalents ions will be 8/8 and number of octahedral voids are 4 so one half would be 2 finally, AB2O4.

• ## Question: Two point masses of 0.3kg and 0.7kg are fixed at the ends of a rod of length 1.4...

Posted in: Physics | Date: 16/12/2017

Ans- 0.98 m from mass of 0.3 kg.

• ## Question: A uniform cylinder of length L and mass M having cross-sectional area A is suspe...

Posted in: Physics | Date: 16/12/2017

At equilibrium ΣF=0ΣF0 kx0+(AL2σg)−0AL2σg Mg =0 x00 = Mg [1−LAσ2M]

• ## Question: How much time is required to learn basic spoken english

Posted in: Effective Communication | Date: 17/12/2017

It’s a question that is almost impossible to answer because it depends on so many different factors. According to English UK, it takes about 120 hours to progress from one level to the next.... Cambridge ESOL suggests slightly longer: 200 hours.

• ## Question: What is the difference between afraid and scared?

Posted in: Effective Communication,Spoken English | Date: 17/12/2017

To be afraid of something means the fear is inside you whereas to be scared of someone denotes that is it external fear.

• ## Question: Which is the best book for English Vocabulary?

Posted in: Effective Communication | Date: 17/12/2017

Read dictionary and when you dont know the meaning of any word google it immediately ...

• ## Question: What speed should a galaxy move with respect to us so that the sodium line at 58...

Posted in: Physics | Date: 18/12/2017

Solution : λ=589nmλ589nm Δλ=589.6−589.0Δλ589.6589.0 =0.6nm0.6nm V=ΔλλVΔλλ =0.65890.6589×3×108m/s3108ms =3.06×105m/s3.06105ms =30.6km/s

• ## Question: Help me to differentiate between the red shift and the blue shift?

Posted in: Physics | Date: 18/12/2017

When something is moving away from something else, the light that is emitted is predominantly at the red end of the spectrum. Red light wavelengths tend to be more stretched out the futher you are from the object. Blue light wavelengths tend to be closer together. Blueshift light tends to be emitted from objects that are moving closer. By looking at the blue and red shift, we can determine whether the object is coming closer to us such as in the case of the Andromeda galaxy or moving away from us.

• ## Question: What is linearly polarised light?

Posted in: Physics | Date: 18/12/2017

In electrodynamics, linear polarization or plane polarization of electromagnetic radiation is a confinement of the electric field vector or magnetic field vector to a given plane along the direction of propagation. The orientation of a linearly polarized electromagnetic wave is defined by the direction of the electric field vector. For example, if the electric field vector is vertical (alternately up and down as the wave travels) the radiation is said to be vertically polarized.

• ## Question: Light waves can be polarized while sound waves cannot be. Why?

Posted in: Physics | Date: 18/12/2017

Sound waves are longitudinal. Only transverse waves can be polarised. Longitudinal waves cannot be polarised. Transverse: vibrations perpendicular to the direction of travel of the wave . Longitudinal: vibrations parallel to the direction of travel of the wave. Sound waves are longitudinal so they cannot be polarised. Polarised: the wave vibrations occur in one plane only Unpolarised: the wave vibrations occur in all planes perpendicular to the direction of travel. The reason that only transverse waves can be polarised is that their vibrations can potentially occur in all directions perpendicular to the direction of travel. It is therefore possible to confine the vibrations to a single plane. Or put another way an unpolarised transverse wave is a 3D shape, it is therefore possible to confine it to a 2D shape (a plane). The vibrations of a longitudinal wave occur along a single line, it is therefore not possible to confine that to a plane, i.e. a 1D shape cannot be confined within a 2D shape.

• ## Question: One of the followings is a naturally occurring compound which reduces the sensat...

Posted in: Biology | Date: 18/12/2017

C- Endorphin

• ## Question: Why is diffraction common in sound but not in light?

Posted in: Physics | Date: 18/12/2017

As a general guide, if we consider diffraction of a wave with wavelength λλ from an object of size dd then the characteristic angle of the diffraction is given by: sinθ=O(λd) sinθOλd where the O()O symbol means of order i.e. roughly the same as. So for example in a Young's slits experiment, where dd is the slit spacing, the angle of the first maximum is given by: sinθ=λd sinθλd Alternatively, the diffraction pattern from a pinhole of diameter dd has the first minimum at: sinθ≈1.22λd sinθ1.22λd It should now be obvious why diffraction of sound is so commonly observed in everyday life. The wavelength of sound is of order one metre, so objects around a metre in size will diffract it strongly. By contrast the wavelength of light is around half a micron, so you need to get the size down to the micron scale before light starts scattering strongly.

• ## Question: How is diffraction effect suppressed in young’s double slit experiment?

Posted in: Physics | Date: 18/12/2017

Both diffraction and interference occur in the double slit experiment. The wavefront is diffracted as it passes through each of the slits. The diffraction causes the wavefronts to spread out as if they were coming from light sources located at the slits. These two wavefronts overlap, and interference occurs. This is what give the diffraction pattern. I think what you are confused about is the single slit experiment. In the single slit experiment, light passes through a single slit which produces an interference pattern. This not do to diffraction of the light. In the single slit experiment, the slit is large enough that diffraction does not occur. Instead every point along the width of the slit acts like it's own point light source, which all interfere with one another. In fact, if you make the slit narrow enough in the single slit experiment, diffraction occurs and the interference pattern goes away.

• ## Question: Why is no interference pattern observed when two coherent sources are: a) Infin...

Posted in: Physics | Date: 18/12/2017

Fringe width is inversely proportional to the distance (d) between the sources. When coherent sources are placed very close, fringe width is very large and a single fringe may occupy the whole field of view and the pattern would not be detected. Similarly, if the coherent sources are far apart, fringe with will be very small and the pattern cannot be detected.

• ## Question: When a low-flying aircraft passes overhead, we notice a slight shaking of the pi...

Posted in: Physics | Date: 18/12/2017

A low flying aircraft reflects the T.V screen can be due to interference between the direct signal and the reflected signal. So May be due to interference between the direct and reflected signal...

• ## Question: Can two independent sources of light be coherent?

Posted in: Physics | Date: 18/12/2017

usually generate light by black body radiation, that is by heating something until it glows. There are many sources for black body radiation, but the dominant one is usually random thermal motion causing random transient electric dipoles within the black body. The changes in these dipoles generates eletromagnetic radiation, and because the dipole changes are random so is the EM radiation they generate. If you take two points in the black body that are close compared to the wavelength of the lattice vibrations then their motion, and hence the EM generated, will be closely correlated. However as you increase the separation between the two points the correlation will decrease and at macroscopic distance will be essentially zero.

• ## Question: What determines the intensity of light in the photon picture of light?

Posted in: Physics | Date: 18/12/2017

Intensity of a wave(carrier of energy) is defined as the energy crossing per unit area per second(Power/Area). Intensity of a particle(Photon,quantum of energy) is defined the flux of no. of particles per second(means no. of photons passing per area per time). So in the photon picture of light if no. of photons increases then intensity of light increases. Albert Einstein used this concept to describe photo-electric effect. He proposed that a photon collides with a single electron and transfers its all energy to the electron and electron leaves the metal surface. So if intensity of light is increased then more photon will incident on the surface and so more electrons will emerge.

• ## Question: Why is the contribution of the wavelets lying on the back of the wave front zero...

Posted in: Physics | Date: 18/12/2017

That is because of a term called the Obliquity Factor. It is assumed that the amplitude of the secondary wavelets is not independent of the direction of propagation. That is the amplitude is not uniform in all directions. The amplitude of the secondary wavelets goes as 1+cosθ1cosθ, where θθ is the angle made from the direction of motion. So, when θ=0θ0, that is along the direction of propagation of the wave, then the amplitude contribution of the secondary wavelets is maximum. However, if θ=πθπ, then the amplitude contribution is zero.

• ## Question: What is current? What is its SI unit?

Posted in: Physics | Date: 18/12/2017

An electric current is a flow of electric charge. In electric circuits this charge is often carried by moving electrons in a wire. It can also be carried by ions in an electrolyte, or by both ions and electrons such as in an ionised gas (plasma). The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second. Electric current is measured using a device called an ammeter. Electric currents cause Joule heating, which creates light in incandescent light bulbs. They also create magnetic fields, which are used in motors, inductors and generators. The moving charged particles in an electric current are called charge carriers. In metals, one or more electrons from each atom are loosely bound to the atom, and can move freely about within the metal. These conduction electrons are the charge carriers in metal conductors.

• ## Question: What is the cause of resistance and on what factors does it depend?

Posted in: Physics | Date: 18/12/2017

It depends on the direction magnetic field if the field is in direction of electric field then the resistance will decrease because all domains of conductor are arranged in direction of electric field and resistance decreases.

• ## Question: The organ of corti is a structure present in.

Posted in: Biology | Date: 18/12/2017

D - Cochlea The organ of Corti or spiral organ, is the receptor organ for hearing and is located in the mammalian cochlea. This highly varied strip of epithelial cells allows for transduction of auditory signals into nerve impulses' action potential.

• ## Question: Which one of the followings is the function of parasympathetic nervous system?

Posted in: AIPMT | Date: 18/12/2017

The parasympathetic system is responsible for stimulation of "rest-and-digest" or "feed and breed" activities that occur when the body is at rest, especially after eating, including sexual arousal, salivation, lacrimation (tears), urination, digestion and defecation. Its action is described as being complementary to that of the sympathetic nervous system, which is responsible for stimulating activities associated with the fight-or-flight response.

• ## Question: A light pulse is sent through a medium. Will it retain its shape?

Posted in: Physics | Date: 18/12/2017

Depends on the medium. Pure glass, sure the photons just pass on through with little resistance and coupling.

• ## Question: Which portion of the brain is responsible for various emotions such as pleasure,...

Posted in: Biology | Date: 18/12/2017

D- limbic system. Emotions like pleasure, fear and brain are carried out by the limbic system, located in the temporal lobe.

• ## Question: Why is diffraction not observed when a wide slit is illuminated by monochromatic...

Posted in: Physics | Date: 18/12/2017

In diffraction grating, the spectrum of the light obtained is very sharp and clear than that of two slit. This helps for precise measurement of wavelength of the monochromatic light. So, diffraction grating is better than two slits set up for measuring the wavelength of monochromatic light.

• ## Question: What was the basic idea suggested by the corpuscular theory of Newton? What was ...

Posted in: Physics | Date: 18/12/2017

In optics, the corpuscular theory of light, arguably set forward by Descartes (1637) states that light is made up of small discrete particles called "corpuscles" (little particles) which travel in a straight line with a finite velocity and possess impetus. This was based on an alternate description of atomism of the time period.This theory cannot explain refraction diffraction,interference and polarization.Newton was the pioneer of this theory.

• ## Question: The normality of orthophosphoric acid having purity of 70% by weight and specifi...

Posted in: AIPMT | Date: 18/12/2017

C-33N. Mass =70 %*1.54 =1.078 g/ml Mass in 1000 ml solution=1.078*1000=1078 g Molar mass of orthophosphoric acid=98 g Normality of orthophosphoric acid=(Mass of solute in 1L)/(Molar mass/basicity) =(1.078)/(98/3) =33 N So,the normality of orthophosphoric acid having purity of 70 % by weight and specific gravity 1.54 is 33N.

• ## Question: An aqueous solution of 6.3 g of oxalic acid dihydrate is made up of to 250 ml. T...

Posted in: Chemistry | Date: 18/12/2017

A-40ml. Oxalic acid dehydrate H2C2O4 . 2H2O : mw = 126 It is a dibasic acid, hence equivalent weight = 63 ⇒ Normality = 6.3/63 × 1000/250 = 0.4 N ⇒ N1V1 = N2V2 0.1 ×V1 = 0.4 × 10 Hence, V1 = 40 mL.

• ## Question: A plane mirror reflecting a ray of incident light is rotated through an angle $$... Posted in: AIPMT | Date: 18/12/2017 ### Answer: C- The reflected ray rotates through an angle 2θ. A ray of light is reflected by an angle (angle of incidence or angle of reflection; since both are equal) about the normal after reflection. Now, when the mirror itself is rotated by theta, the normal also rotates by theta. So the ray of light is reflected at an angle theta about the Normal. Hence the total angle becomes: theta(angle between the incident ray and normal) + theta ( angle between the normal and the reflected ray)=2*theta. • ## Question: The resistance of a wire is 10\(\Omega$$ . Its length is increased by 10% by str...

Posted in: Physics | Date: 18/12/2017

When we stretch a wire, its length increases but its area of cross section also decreases. However the volume of the wire remans constant. If L1 is the initial length L2 is the final length, A1 is the original area of cross section and A2 is the final area of cross section we have L1A1 = L2A2 = V. We know that the resistance R1 = rho L1/A1 = rho L1 X L1 /L1 X A1 = rho L1^2/V Similarly R2 = rho L2^2/V Dividing we get R2/R1 = (L2) ^2 /(L1) ^2 = (1.1 )^2 = 1.21 since L2 is 10 percent longer than L1 So R2 = 1.21 R1 = 1.21 x 10 = 12.1 ohms

• ## Question: Every atom makes one free electron in copper. If 1.1 ampere current is flowing i...

Posted in: Physics | Date: 18/12/2017

B-0.1 mm/sec. Density of Cu=9×103kg/m3 (mass of 1 m3 of Cu) 6.0×1023 atoms has a mass = 63×103kg \ Number of electrons per m3are =6.0×102363×10−3×9×103=8.5×1028 Now drift velocity =vd=ineA =1.18.5×1028×1.6×10−19×π×(0.5×10−3)2 =0.1×10−3m/sec...

• ## Question: Two equally charged, identical metal spheres A and B repel each other with a for...

Posted in: AIPMT | Date: 18/12/2017

Consider the two identical sphere A and B each having charge q are placed at a distance r apart as shown below. Now, ... (1) [5×0.00005 N = 5×10-5 N] When an identical uncharged sphere C is touched to A, both will share the charge on A equally i.e., each of the spheres A and C will now possess charge q/2. The sphere C placed at the mid point between A and B experiences forces FCA (due to sphere A) and FCB (due to sphere B) in the directions as shown in the figure below. Now, and Since FCB>FCA, the resultant force on the sphere C is given by, Using eqn (1), we have, F' = 5×10-5 N (along CA)

• ## Question: Two spherical conductors B and C having equal radii and carrying equal charges i...

Posted in: Physics | Date: 18/12/2017

when 2 identicle metalic surface bought in contact then charge onn them are equalised due to the flow of free elctron let the initial charge on B and C is q when third sphere come in contact with B then new charge on B =q/2 and charge on the third conductor =q/2 and third conductor come in contact with C so total charge =q/2 + q =3q/2 charge will equally distribute ,so charge on C = 3q/4 now force = k (q/2)(3q/4) /d2 = 3F/8

• ## Question: The molar heat capacity in a process of a diatomic gas if it does a work of Q/4 ...

Posted in: AMIE | Date: 18/12/2017

C-10/3R. From the First law of Thermodynamics we have :- Q=w+ΔU(1) (1) QwΔU where, QQ = Heat supplied to the gas ww = Work done by the gas ΔUΔU = Change in the internal energy of the gas Given :- w=Q4(2) (2) wQ4 From (1)1 & (2)2 we have :- ⟹ΔU=3Q4(3) (3) ΔU3Q4 Now, ΔU=nRΔTγ−1(4) (4) ΔUnRΔTγ1 where, nn = No. of moles of gas ΔTΔT = Change in temperature RR = Universal Gas Constant γγ = Specific heat ratio For a diatomic gas :- γ=75(5) (5) γ75 Using (3)3, (4)4 & (5)5 we get :- ⟹nΔT=3Q10R(6) (6) nΔT3Q10R Also note that :- Q=nCΔT(7) (7) QnCΔT where, CC = Molar specific heat for the process So now replace nΔTnΔT in (7)7 by (6)6 :- ⟹3QC10R=Q3QC10RQ ⟹C=10/3R

• ## Question: A mono atomic gas is supplied the heat Q very slowly keeping the pressure consta...

Posted in: Physics | Date: 18/12/2017

A-2/3 Q. For monoatomic gas at constant pressure: ΔUQ=13⇒ΔU=Q3ΔUQ13ΔUQ3 From 1st law of thermodynamics: W=ΔQ−ΔU=Q−Q/3= 2Q/3

• ## Question: A particle executes S.H.M. in a line 4 cm long. It's velocity when passing t...

Posted in: AMIE | Date: 18/12/2017

B-1.047 s. Length of the line = Distance between extreme positions of oscillation = 4 cm So, Amplitude a=2cm. also vmax=12cm/s. ∵vmax=ωa=2πTa ⇒T=2πavmax=2×3.14×212=1.047sec

• ## Question: A man draws a card from a pack of 52 cards and then replaces it. After shuffling...

Posted in: AMIE | Date: 19/12/2017

Since card is replaced everytime, Therefore the probability of picking a card of hearts is 13/52 = 1/4 each time a card is drawn. Now, Probability that atleast 3 trials are needed = 1 - (P[1 trial is needed] + P[2 trials are needed]) P[2 trials] = 1st trial gives non-heart card and 2nd trial gives a heart card = 1 - (1/4 + (3/4 * 1/4)) = 1 - (1/4 + 3/16) = 1 - 7/16 = 9/16 = 0.5625 Therefore, Required Probability = 0.5625

• ## Question: When electric current is passed through a cell containing the electrolyte + ve i...

Posted in: Chemistry | Date: 19/12/2017

D--+ ve ions and – ve ions will start moving randomly. In the absence of electric field the ions in the solution move randomly due to thermal energy.

• ## Question: Which of the following characteristic is wrong for physical adsorption? Please h...

Posted in: Chemistry | Date: 19/12/2017

D- none of above. During adsorption, there is always decrease in surface energy which appears as heat. Therefore adsorption always takes place with evolution of heat, i.e. it is an exothermic process and since the adsorption process is exothermic, the physical adsorption occurs readily at low temperature and decreases with increasing temperature. (Le Chatelier's principle).

• ## Question: The size of the image of an object, which is at infinity, as formed by a convex ...

Posted in: AIPMT | Date: 19/12/2017

B-2.5 cm. SOLUTION HINT : For concave lens 1/v−1/4=1/-20 v = 5 cm h2/h1=|v|/|u|⇒h2=2×5/4=2.5 cm

• ## Question: When an object is at distances u$$_1$$ and u$$_2$$ from a convex lens,...

Posted in: Physics | Date: 19/12/2017

1/v1 + 1/u1 = 1/f1 ….(1) When an image is virtual 1/(-v2) + 1/u2 = 1/f ….(2) From equation (1) V1 = u1f/ u1 – f Or, v1/u1 = f/u1 –f = magnification (m) From equation (2) V2 = u2f/ f –u2 Or, v2/u2 = f/f-u2 = magnification (m1) If m = m1 Or, f/u1 –f = f/f-u2 Or, f = u1 + u2/2 = Focal length

• ## Question: A metal ball immersed in alcohol weighs W$$_1$$ at 0$$^0$$ C and W$$_2$$ at...

Posted in: AIPMT | Date: 19/12/2017

B- W1=W2 . At 70 degrees the liquid converts to a different liquid having some density other than that of alochol. Now the law of buoyancy doesn't change on changing the density of liquid. So, W1=W2.

• ## Question: A tetrahedral site in a closest packed lattice can be generated by placing four ...

Posted in: AMIE | Date: 19/12/2017

B-2R. Since the spheres are in contact at the centre of each cube face, fd = 2 R.

• ## Question: In Bessemer and Thomas processes of extraction of iron, lining of the convertor ...

Posted in: AIPMT | Date: 19/12/2017

A- phosphorus. Solution: P4O10 + 6Fe + 3O2 2Fe3(PO4)2 Fe3(PO4)2 + 2Fe3C + 3Fe 2Fe3P + 6FeO + 2CO FeO + SiO2 FeSiO3 (furnace lining)

• ## Question: What is self inductance?

Posted in: Physics | Date: 19/12/2017

Whenever the current flowing through a coil changes, an emf is generated across it. This induced emf is proportional to the change in current. ie EMF α dI/dt The constant of proportionality is called Self Indusctance (denoted by L) and measured in Henry. EMF =- L (dI/dt) The negative sign indicates the EMF generated is opposite to the flow of current

• ## Question: Help me to derive an expression for the mutual inductance of two long coaxial so...

Posted in: Physics | Date: 19/12/2017

Suppose a current i is passed through the inner solenoid . A magnetic field is produce inside whereas field outside it is zero. is permeability of vaccum. Let and be the no of turns it each solenoid of equal length l. Therefore, flux through each turn of solenoid is The total flux through all the turns in a length l of is And we know that where M is the mutual inductance. Therefore mutual inductance of two long coaxial solenoids of same lenth...

• ## Question: How does the self inductance of an air core coil change, when  (a) the n...

Posted in: Physics | Date: 19/12/2017

The relative permeability of iron compared to air is about 200. Thus, introduction of iron core will magnify the inductance by 200 times compared to air core. In other words, inductance will increase 200 times.

• ## Question: What are the suggested reasons for population explosion?

Posted in: Biology | Date: 20/12/2017

The human population is increasing day by day, leading to population explosion. It is because of the following two major reasons. (a) Decreased death rate (b) Increased birth rate and longevity The death rate has decreased in the past 50 years. The factor leading to decreased death rate and increased birth rate are control of diseases, awareness and spread of education, improvement in medical facilities, ensured food supply in emergency situation, etc. All this has also resulted in an increase in the longevity of an individual.

• ## Question: Suggest the aspects of reproductive health which need to be given special attent...

Posted in: NEET | Date: 20/12/2017

Reproductive health is the total well being in all aspects of reproduction. The aspects which have to be given special attention in the present scenarios are (1)Counselling and creating awareness among people, especially the youth, about various aspects of reproductive health, such as sexually transmitted diseases, available contraceptive methods, case of pregnant mothers, adolescence, etc. (2)Providing support and facilities such as medical assistance to people during pregnancy, STDs, abortions, contraceptives, infertility, etc. for building a reproductively healthy society

• ## Question: What do you think is the significance of reproductive health in a society?

Posted in: Physics | Date: 20/12/2017

Reproductive health is the total well being in all aspects of reproduction. It includes physical, emotional, behavioural, and social well being. Sexually transmitted diseases such as AIDS, gonorrhoea, etc. are transferred from one individual to another through sexual contact. It can also lead to unwanted pregnancies. Hence, it is necessary to create awareness among people, especially the youth, regarding various reproduction related aspects as the young individuals are the future of the country and they are most susceptible of acquiring sexually transmitted diseases. Creating awareness about the available birth control methods, sexually transmitted diseases and their preventive measures, and gender equality will help in bringing up a socially conscious healthy family. Spreading awareness regarding uncontrolled population growth and social evils among young individuals will help in building up a reproductively healthy society.

• ## Question: What is apomixis and what is its importance?

Posted in: Biology | Date: 20/12/2017

Apomixis is the mechanism of seed production without involving the process of meiosis and syngamy. It plays an important role in hybrid seed production. The method of producing hybrid seeds by cultivation is very expensive for farmers. Also, by sowing hybrid seeds, it is difficult to maintain hybrid characters as characters segregate during meiosis. Apomixis prevents the loss of specific characters in the hybrid. Also, it is a cost-effective method for producing seeds.

• ## Question: Help me to explain the role of tapetum in the formation of pollen-grain wall.

Posted in: Biology | Date: 20/12/2017

Tapetum is the innermost layer of the microsporangium. It provides nourishment to the developing pollen grains. During microsporogenesis, the cells of tapetum produce various enzymes, hormones, amino acids, and other nutritious material required for the development of pollen grains. It also produces the exine layer of the pollen grains, which is composed of the sporopollenin.

• ## Question: If one can induce parthenocarpy through the application of growth substances, wh...

Posted in: NEET | Date: 20/12/2017

Parthenocarpy is the process of developing fruits without involving the process of fertilization or seed formation. Therefore, the seedless varieties of economically important fruits such as orange, lemon, water melon etc. are produced using this technique. This technique involves inducing fruit formation by the application of plant growth hormones such as auxins.

• ## Question: What is meant by emasculation? When and why does a plant breeder employ this te...

Posted in: Biology | Date: 20/12/2017

Emasculation is the process of removing anthers from bisexual flowers without affecting the female reproductive part (pistil), which is used in various plant hybridization techniques. Emasculation is performed by plant breeders in bisexual flowers to obtain the desired variety of a plant by crossing a particular plant with the desired pollen grain. To remove the anthers, the flowers are covered with a bag before they open. This ensures that the flower is pollinated by pollen grains obtained from desirable varieties only. Later, the mature, viable, and stored pollen grains are dusted on the bagged stigma by breeders to allow artificial pollination to take place and obtain the desired plant variety.

• ## Question: Why is apple called a false fruit? Which Part(s) of the flower forms the fruit?

Posted in: NEET | Date: 20/12/2017

Fruits derived from the ovary and other accessory floral parts are called false fruits. On the contrary, true fruits are those fruits which develop from the ovary, but do not consist of the thalamus or any other floral part. In an apple, the fleshy receptacle forms the main edible part. Hence, it is a false fruit.

• ## Question: Why do you think the zygote is dormant for sometime in a fertiUsed ovule?

Posted in: Biology | Date: 20/12/2017

The zygote is formed by the fusion of the male gamete with the nucleus of the egg cell. The zygote remains dormant for some time and waits for the endosperm to form, which develops from the primary endosperm cell resulting from triple fusion. The endosperm provides food for the growing embryo and after the formation of the endosperm, further development of the embryo from the zygote starts.

• ## Question: What b triple fusion? Where and how does it take place? Name the nuclei involved...

Posted in: Biology | Date: 20/12/2017

Triple fusion is the fusion of the male gamete with two polar nuclei inside the embryo sac of the angiosperm. This process of fusion takes place inside the embryo sac. When pollen grains fall on the stigma, they germinate and give rise to the pollen tube that passes through the style and enters into the ovule. After this, the pollen tube enters one of synergids and releases two male gametes there. Out of the two male gametes, one gamete fuses with the nucleus of the egg cell and forms the zygote (syngamy). The other male gamete fuses with the two polar nuclei present in the central cell to form a triploid primary endosperm nucleus. Since this process involves the fusion of three haploid nuclei, it is known as triple fusion. It results in the formation of the endosperm. One male gamete nucleus and two polar nuclei are involved in this process.

• ## Question: What is bagging technique? How is it useful in a plant breeding programme?

Posted in: Biology | Date: 20/12/2017

Various artificial hybridization techniques (under various crop improvement programmes) involve the removal of the anther from bisexual flowers without affecting the female reproductive part (pistil) through the process of emasculation. Then, these emasculated flowers are wrapped in bags to prevent pollination by unwanted pollen grains. This process is called bagging. This technique is an important part of the plant breeding programme as it ensures that pollen grains of only desirable plants are used for fertilization of the stigma to develop the desired plant variety.

• ## Question: What is self-incompatibility? Why does self-pollination not lead to seed formati...

Posted in: Biology | Date: 20/12/2017

Self-incompatibility is a genetic mechanism in angiosperms that prevents self-pollination. It develops genetic incompatibility between individuals of the same species or between individuals of different species. The plants which exhibit this phenomenon have the ability to prevent germination of pollen grains and thus, prevent the growth of the pollen tube on the stigma of the flower. This prevents the fusion of the gametes along with the development of the embryo. As a result, no seed formation takes place.

• ## Question: What are chasmogamous flowers? Can cross-pollination occur in cleistogamous flow...

Posted in: NEET | Date: 20/12/2017

There are two types of flowers present in plants namely Oxalis and Viola − chasmogamous and cleistogamous flowers. Chasmogamous flowers have exposed anthers and stigmata similar to the flowers of other species. Cross-pollination cannot occur in cleistogamous flowers. This is because cleistogamous flowers never open at all. Also, the anther and the stigma lie close to each other in these flowers. Hence, only self-pollination is possible in these flowers.

• ## Question: With a neat diagram explain the 7-celled, 8- nucleate nature of the female gamet...

Posted in: Biology | Date: 20/12/2017

The female gametophyte (embryo sac) develops from a single functional megaspore. This megaspore undergoes three successive mitotic divisions to form eight nucleate embryo sacs. The first mitotic division in the megaspore forms two nuclei. One nucleus moves towards the micropylar end while the other nucleus moves towards the chalazal end. Then, these nuclei divide at their respective ends and re-divide to form eight nucleate stages. As a result, there are four nuclei each at both the ends i.e., at the micropylar and the chalazal end in the embryo sac. At the micropylar end, out of the four nuclei only three differentiate into two synergids and one egg cell. Together they are known as the egg apparatus. Similarly, at the chalazal end, three out of four nuclei differentiates as antipodal cells. The remaining two cells (of the micropylar and the chalazal end) move towards the centre and are known as the polar nuclei, which are situated in a large central cell. Hence, at maturity, the female gametophyte appears as a 7-celled structure, though it has 8 nucleate.

• ## Question: What is meant by monosporic development of female gametophyte?

Posted in: Biology | Date: 20/12/2017

The female gametophyte or the embryo sac develops from a single functional megaspore. This is known as monosporic development of the female gametophyte. In most flowering plants, a single megaspore mother cell present at the micropylar pole of the nucellus region of the ovule undergoes meiosis to produce four haploid megaspores. Later, out of these four megaspores, only one functional megaspore develops into the female gametophyte, while the remaining three degenerate.

• ## Question: What is % bisexual flower?

Posted in: Biology | Date: 20/12/2017

A flower that contains both the male and female reproductive structure (stamen and pistil) is called a bisexual flower. Examples of plants bearing bisexual flowers are: (1) Water lily ( Nymphaea odorata) (2) Rose (Rosa multiflora ) (3) Hibiscus (Hibiscus Rosa-sinensis ) (4) Mustard ( Brassica nigra) (5) Petunia (Petunia hybrida)

• ## Question: Help me to differentiate between a zoospore and a zygote.

Posted in: Biology | Date: 20/12/2017

Zoospore...zygote 1. A zoospore is a motile asexual spore that utilizes the flagella for movement. A zygote is a non-motile diploid cell formed as a result of fertilization. 2. It is an asexual reproductive structure. It is formed as a result of sexual reproduction.

• ## Question: Why is no interference pattern observed when two coherent sources are (i) infini...

Posted in: Physics | Date: 21/12/2017

Fringe width is inversely proportional to the distance (d) between the sources. When coherent sources are placed very close, fringe width is very large and a single fringe may occupy the whole field of view and the pattern would not be detected. Similarly, if the coherent sources are far apart, fringe with will be very small and the pattern cannot be detected.

• ## Question: Sun glasses are made of polaroids and not of coloured glasses. Why?

Posted in: Physics | Date: 21/12/2017

because the polaroids reduce the intensity of sunlight and makes u feel comfortable.. Thus this concept is used

• ## Question: If the polarizing angle for air-glass inter- face is 56.3$$^o$$, what is the ang...

Posted in: Physics | Date: 21/12/2017

At polarising angle, ip+rp=90°... rp=90−ip=90−55.3 =34.7

• ## Question: Does the value of polarising angle of incidence depend on the colour of light?

Posted in: Physics | Date: 21/12/2017

The refractive index of a material depends on the wavelength of the light. As the polarising angle depends on the refractive index, it also depends on the wavelength of the light.

• ## Question: Why does the electric field of e. m. wave determine the state of polarisation an...

Posted in: Physics | Date: 21/12/2017

The polarization of an electromagnetic wave follows the direction of the electric field. For example, if the electric component is oscillating along the x-axis and the magnetic field is oscillating in the y-axis, the polarization will be along the x-axis.

• ## Question: Which plane is defined as the plane of polarization in a plane polarized electro...

Posted in: Physics | Date: 21/12/2017

Plane of vibration : The vibrations of EM wave occuring in a plane. This plane is always perpendicular to the plane of polarisation.

• ## Question: Why longitudinal waves cannot be polarised?

Posted in: Physics | Date: 21/12/2017

For longitudinal waves the direction of propagation is parallel to the direction of travel and they cannot be polarized, for transverse the direction of travel is perpendicular to the direction of propagation and they can be polarized..

• ## Question: A single slit diffraction pattern is completely immersed in water without changi...

Posted in: Physics | Date: 21/12/2017

Solution : Wave length of light in water (λ′=λ/μ) decreases.... So width of central maximum (β0αλ) also decreases...

• ## Question: A small circular disc is placed in the path of light from a distant source. Will...

Posted in: Physics | Date: 21/12/2017

waves diffracted from the edge of circular obstacle interfere constructive at the center of the shadow resulting in the formation of a bright spot .

• ## Question: How does the angular separation between fringes in single-slit diffraction exper...

Posted in: Physics | Date: 21/12/2017

Angular separation between diffraction fringe θ=β/D When the distance D is doubled the angular separation θθ remains unchanged

• ## Question: What should be the order of size of obstacle or aperture for diffraction of ligh...

Posted in: Physics | Date: 21/12/2017

The size of the slit should be of the order of the wavelength of the light used.

• ## Question: The central fringe obtained with a Lloyd's mirror set up for interference is...

Posted in: Physics | Date: 21/12/2017

The central fringe obtained with a Lloyd's mirror is dark because the reflection of light from the denser mirror surface introduces a path difference ofλ/2. In case of biprism, the waves from both the coherent sources reach the central point in the same phase so the central fringe is bright.

• ## Question: Why is it comparatively difficult to observe interference in light waves as comp...

Posted in: Physics | Date: 21/12/2017

This is because the wavelength of light waves is much smaller than the wavelength of water waves. Consequently, the interference fringes have much smaller width in case of light waves than in water waves.

• ## Question: What will be the effect on the fringes formed in Young's double slit experim...

Posted in: Physics | Date: 21/12/2017

The wavelength of light in water (λ′=λ/μ)is less than that in air. When the apparatus is immersed in water, fringe width(β∝λ′) decreases.

• ## Question: What happens to the light energy when light waves interfere destructively at a p...

Posted in: Physics | Date: 21/12/2017

Energy gets transferred from the regions of destructive interference to the regions of constructive interference.

• ## Question: How will the intensity of maxima and minima, in the Young's double slit expe...

Posted in: Physics | Date: 21/12/2017

Intensity of maxima decreases and that of minima increases.

• ## Question: When a thin transparent film is Placed just in front of one of the slits in the ...

Posted in: Physics | Date: 21/12/2017

Ifμ is-the refractive index and t the thickness of the thin film, then the entire interference pattern gets displaced by distance, Δx=D/d(μ−1)t As μ depends on λ (increases with decreasing λ), the violet fringe is shifted farther than the red fringe. So there is a kind of dispersion in the central white fringe.

• ## Question: If the path difference produced due to interference of light coming out of two s...

Posted in: NEET | Date: 21/12/2017

The given path difference satisfies condition for the minimum of intensity for yellow Hence if yellow light is used, a dark fringe will be formed at the given point. If white light is used, all components white light except the yellow one would be present a point.

• ## Question: Why is interference pattern not detected when the two coherent sources are far a...

Posted in: Physics | Date: 21/12/2017

When the distance d between the coherent sources is large, the fringe width (β∝1/d) becomes too small to be detected. The interference pattern cannot be observed.

• ## Question: No interference pattern is detected when two coherent sources are infinitely clo...

Posted in: Physics | Date: 21/12/2017

Fringe width, β=λD/d i.e., β∝1/d, when d→0,β→∞. Fringe width is very large. Even a single fringe occupy the entire screen. The interference pattern cannot be observed.

• ## Question: In Young's double slit experiment if the distance between two slits is halve...

Posted in: Physics | Date: 21/12/2017

Original fringe width, β=λD/d New fringe width, β′=λ.2D/d/2=4×D/d=4β i.e., fringe width increases four times.

• ## Question: Why should we have a narrow source to produce good interference fringes?

Posted in: NEET | Date: 21/12/2017

It is because a broad source is equivalent to a large number of narrow sources lying close to each other. Different pairs of narrow sources will produce their own interference patterns which will overlap each other. So the fringe system is lost.

• ## Question: How does the fringe width, in Young's double-slit experiment, change when th...

Posted in: Physics | Date: 21/12/2017

Fringe width, β=Dλ/d When the distance D between the slits and the screen is doubled, the fringe width also gets doubled.

• ## Question: If the separation between the two slits is decreased in Young's double slit ...

Posted in: Physics | Date: 21/12/2017

Fringe width, β=Dλ/d As the separation 'd' between the two slits decreases, fringe width β increases.

• ## Question: Two independent light sources cannot act as coherent sources'. Why?

Posted in: Physics | Date: 21/12/2017

Two independent sources of light cannot be coherent. This is because light is emitted by individual atoms, when they return to ground state. Even the smallest source of light contains billions of atoms which obviously cannot emit light waves in the same phase.

• ## Question:  Why are coherent sources necessary to produce a sustained interference pat...

Posted in: Physics | Date: 21/12/2017

Coherent sources have a constant phase difference. This ensures that the positions of maxima and minima do not change with time i.e., a sustained interference pattern is obtained.

• ## Question: What happens to the interference pattern if the phase difference between the two...

Posted in: Physics | Date: 21/12/2017

The positions of bright and dark fringes will change rapidly. Such rapid changes cannot be detected by our eyes. A uniform illumination is seen on the screen i.e., interference pattern disappears.

• ## Question: Help me to state two conditions to obtain sustained interference of light.

Posted in: Physics | Date: 21/12/2017

The conditions for obtaining sustained interference of light are (i) The two light sources should be coherent, (ii) The two light sources should be narrow and placed close to each other.

• ## Question: What is the term 'coherence' for light waves.

Posted in: Physics | Date: 21/12/2017

Two light waves interfering with each other are said to show coherence if the initial phase difference between them remains constant with time.

• ## Question: When monochromatic light travels from one medium to another its wavelength chang...

Posted in: Physics | Date: 21/12/2017

Frequency is the characteristic of the source while wavelength is the characteristic of the medium. When monochromatic light travels from one medium to another, its speed changes, so its wavelength (λ=c/v) changes but frequency v remains unchanged.

• ## Question: If a wave undergoes refraction, what will be the phase change?

Posted in: Physics | Date: 21/12/2017

Zero. No phase change occurs during refraction.

• ## Question: When a wave undergoes reflection at a denser medium, what happens to its phase?

Posted in: Physics | Date: 21/12/2017

When a wave is reflected into rarer medium from the surface of a denser medium, it undergoes a phase change of π radian.

• ## Question: A light wave enters from air into glass. How will the following be affected: (i)...

Posted in: Physics | Date: 21/12/2017

(i) Energy of the wave decreases because a part of the light wave is reflected back into air. (ii) Frequency of the wave remains unchanged.

• ## Question: Can two wave-fronts cross one another? Need to give reason.

Posted in: Physics | Date: 21/12/2017

No. If they intersect, then there will be two rays or two directions of propagation of energy at the point of intersection which is not possible.

• ## Question: Is it necessary that the amplitude be constant over a given wave front?

Posted in: NEET | Date: 21/12/2017

Yes. In a homogeneous medium, the amplitude is constant on a given wavefront.

• ## Question: How much is the phase difference corresponding to path difference of &lambd...

Posted in: Physics | Date: 21/12/2017

• ## Question: What are the reasons to believe that light is a wave motion?

Posted in: Physics | Date: 21/12/2017

Light undergoes interference, diffraction and polarisation. These phenomena establish that light is a wave motion.

• ## Question: Difference between b.d and b.tech

Posted in: PG Diploma | Date: 21/12/2017

B.Tech course is somewhat more practically intensive than the BE course which is more theoretical.The difference (which is quite minor) between the two degrees can be understood from their names itself, Engineering Vs. Technology. Engineering is a "science", dealing more with theoretical concepts & principles; technology deals more with the application of these theories for practical purposes. But, both B.E. & B.Tech courses offered by various engineering colleges/ institutes, have similar curriculum more or less. Both degrees are valued equally by prospective employers. What matters more is the reputation of the engineering college from where you obtain your B.E/ B.Tech degree.

• ## Question: If a double stranded DNA has 20 per cent of cytosine, Help me to calculate the p...

Posted in: Biology | Date: 21/12/2017

generally in DNA adenine binds with thymine and guanine binds with cytosine. so if cytosine is 20% then automatically guanine will be 20%. so remaining 60% will be equally distributed in adenine and thymine.. 60/2=30% will be adenine

• ## Question: What are the measures one has to take to prevent from contracting STDs?

Posted in: Biology | Date: 21/12/2017

Avoid sexual intercourse with unknown or multiple partners. Use of condoms during sexual intercourse. Consulting a qualified doctor immediately for treatment in case of doubt of infection.

• ## Question: Find the area of trapezium whose parallel sides 25 cm,13cm and other sides are 1...

Posted in: 3D Printing | Date: 21/12/2017

It's isolated trapezium 1st find area of rectangular base=13 height=x to find height AEC IS RIGHT ANGLE TRIANGLE 6^2+X^2=15^2 X^2=189 X=13.74 area of rectangular=13*13.74=178.72=179 area of 2 triangle=1/2*2*6*13.74=82.44 total area=261.44

• ## Question: What changes in the interference pattern in Young's double slit experiment w...

Posted in: Physics | Date: 21/12/2017

In Young's double slit experiment, the fringe width is given by β=Dλ/d=Dc/dv Clearly, (i) When light of smaller frequency (v) is used, fringe width increases. (ii) Wavelength of light in water decreases, so fringe width (β∝λ) also decreases.

• ## Question: You are able to hear a person standing behind a wall but not see him, though bot...

Posted in: Physics | Date: 21/12/2017

This is because sound waves get easily diffracted round the edge of the wall while light waves do not.

• ## Question: If light bends around obstacles, then why can't we see around a building?

Posted in: Physics | Date: 21/12/2017

The wavelength of light is much smaller than the size of the wall. So diffraction of light around the edge of the wall is very poor. We cannot see around the house.

• ## Question: Radio waves diffract pronouncedly around the buildings, while light waves, which...

Posted in: Physics | Date: 21/12/2017

For diffraction to take place, the wavelength should be of the order of the size of the obstacle. The radio waves (particularly short radio waves) have wavelengths of the order of the size of the building and other obstacles coming in their way and hence they easily get diffracted. Since wavelength of the light waves is very small, they are not diffracted by buildings.

• ## Question: Diffraction is common in sound but not common in light waves? Why? Or Why do we ...

Posted in: NEET | Date: 21/12/2017

Diffraction effect is more pronounced if the size of obstacle or aperture is of the order of the wavelength of the waves. As the wavelength of light( ~10−6m) is much smaller than the size of the objects around us, so diffraction of light is not easily seen. But sound waves have large wavelength. They get easily diffracted by the objects around us.

• ## Question: Is sex education necessary in schools? Why?

Posted in: Biology | Date: 21/12/2017

Sex education in the school must be encouraged as it provides right information’s to the students and in removing certain myths and misconceptions about sex-related aspects existing in their minds. It will also inform them about the causes of occurrence of STDs, AIDS, etc. and also about the safe and hygienic sexual practices.

• ## Question: What is vegetative propagation?

Posted in: NEET | Date: 22/12/2017

Plants part are divided into two parts. vegetative and reproductive parts. Vegetative reproduction is a type of reproduction in which their is no involvement of reproductive parts. Here any part of the plant is cut and with appropriate nutrient and growth hormone condition is able to develop into a fully grown plant. Their are various techniques which are used for vegetative reproduction. Plant should be perennial to be get vegetatively propagated...

• ## Question: Distinguish between asexual and sexual reproduction. Why is vegetative reproduct...

Posted in: Biology | Date: 22/12/2017

For differences between asexual reproduction and sexual reproduction refer image..Vegetative reproduction is considered as a type of asexual reproduction because here also characters of parent plants are preserved. Here propagation takes place where new individual arises from any vegetative part of the parent (root, stem, leaf etc.), and possesses exactly the same characteristics of the parent plant from which it was sampled. Moreover the formation of new individuals does not involve two parents, process involved is asexual.

• ## Question: How does the progeny formed from asexual reproduction differ from those formed b...

Posted in: Biology | Date: 22/12/2017

In asexual reproduction, offsprings are produced by a single parent without the involvement of gamete formation and fusion. Thus offsprings resemble the parent genetically and morphologically. In sexual reproduction, fusion of gametes occur and fertilization and meiosis are essential events. Here, offsprings differ from parents due to appearance of variations.

• ## Question: How many plants in the list given below have composite fruits that develop from ...

Posted in: Biology | Date: 22/12/2017

B-3. Fig, pine apple and mulberry are composite fruits.

• ## Question: A bicollateral vascular bundle has the following arrangement of tissues.

Posted in: Biology | Date: 22/12/2017

C-Outer Phloem - Outer Cambium - Middle Xylem - Inner Cambium - Inner Phloem... A vascular bundle having the phloem strands on both outer and inner sides of xylem is called bicollatoral.

• ## Question: Sequence of cellular layers from the periphery towards the cortex in an old dico...

Posted in: Biology | Date: 22/12/2017

C- Epidermis, Hypodermis, Cortex, Endodermis. Sequence of cellular layers from the periphery towards the cortex in an old dicot stem is epidermis, hypodermis, cortex, endodermis, pericycle and vascular bundles.

• ## Question: 17.Three masses are placed on the x-axis: 300 g at origin, 500 g at x = 40 cm an...

Posted in: Physics | Date: 23/12/2017

D- 40 cm. Solution : xCM=m1x1+m2x2=m3x3/m1+m2+m3 =300(0)+500(40)+400(70)/300+500+400 =20000+28000/1200 =48000/1200 =40cm

• ## Question: 16.A proton carrying 1 MeV kinetic energy is moving in a circular path of radius...

Posted in: AICEE | Date: 23/12/2017

A-1 MeV.

• ## Question: Young’s double slit experiment is first performed in air and then in a med...

Posted in: AICEE | Date: 23/12/2017

D-1.78.

• ## Question: Suppose the charge of a proton and an electron differs lightly. One of them is &...

Posted in: AIPMT | Date: 23/12/2017

C-10-37C.

• ## Question: A gas mixture consists of 2 moles of Oand 4 moles of Ar at temperature T. Neglec...

Posted in: AIPMT | Date: 23/12/2017

Answer : 11RT Explanation : U=n1f1/2RT+n2f2/2RT, f - No.of degrees of freedom f1 for a diatomic gas = 5 f2 for a monoatomic gas = Therefore , U=2×5/2RT+4×3/2RT =11RT

• ## Question: A potentiometer is an accurate and versatile device to make electrical meas...

Posted in: AICEE | Date: 23/12/2017

C- A condition of no current flow through the galvanometer. Because In zero deflection condition, potentiometer draws no current

• ## Question: If the potential energy of a spring when stretched through a distance ‘a&r...

Posted in: Physics | Date: 23/12/2017

900 J. Let the stiffness constant of the spring be k Therefore, the elastic potential energy stored by the spring when it is stretched through a distance of 'a' from its natural length = (1/2) X k X a X a = 25 J (given). So, k X a X a = 50 J Now, the total elastic potential energy stored by the spring when it is stretched through an additional distance of '5a' that is the total distance of '6a' from its natural length = (1/2) X k X 6a X 6a = 18 X k X a X a = 18 X 50 J = 900 J

• ## Question: What is the error in the estimation of g if the length and time period of an osc...

Posted in: Physics | Date: 23/12/2017

Answer: 4% Explanation: We know, Time period (T) of a simple pendulum is related with acceleration due to gravity (g)and length of the pendulum(l) as follows T = 2 π √ l g Squaring and rearranging we get g = 4 π 2 l T 2 Taking log we get log g = log 4 + 2 log π + log l − 2 log T Differentiating we have Δ g g = Δ l l − 2 Δ T T Maximum error ( Δ g g ) max % = Δ l l % + 2 Δ T T % ( Δ g g ) max % = 2 + 2 ⋅ 1 = 4

• ## Question: What fraction of its mechanical energy is lost in each bounce, if a ball bounces...

Posted in: Physics | Date: 23/12/2017

KE¹ = mgh. KE² = mg × 0.8h. KE lost = KE¹- KE² = 0.2mgh . Fraction of KE lost : 0.2mgh/mgh = 0.2 .

• ## Question: If the velocity at the maximum height of a projectile is half its initial veloci...

Posted in: AMITE | Date: 23/12/2017

As ucosθ0=u/2 ∴θo=60° So R=u2sin(2×60°)/g =√3/2 u2/g

• ## Question: What is the number of degree of freedom of a molecule of a diatomic gas at room&...

Posted in: AIEEE | Date: 23/12/2017

A molecule of diatomic gas has five degrees of freedom (3 tanslational and 2 rotational).

• ## Question: Give reason: “Liquid set in rotation comes to rest after some line”.

Posted in: Physics | Date: 23/12/2017

Reason is Viscosity. Explanation : When water in a container or glass tumbler is set into rotation by glass rod , the rotation starts from co-axial cylindrical layers. On stopping the rotation by glass rod, the speed of different layers are seen decreasing and liquid finally comes to rest.Which shows that the liquid experiences a internal friction. Hence Viscosity is the property of fluids by virtue of which an internal resistance or drag[fluid friction ] comes into play when liquid is in motion . The internal friction tries to stop the motion of liquid.

• ## Question: If one mass of one electron is 9.11 x 10$$^{-31}$$kg, then how many electrons wo...

Posted in: Physics | Date: 23/12/2017

Given : mass of an electron=9.11 x 10⁻³¹kg =9.11 x 10⁻²⁸g 1kg=1000g Number of electrons present in 1kg will be : =1000/9.11 x 10⁻²⁸ =109.76 x 10 ²⁸ ∴ Number of electrons present in 1kg would be 109. 76x 10²⁸ electrons.

• ## Question: A body is initially at rest. It undergoes one-dimensional motion with constant a...

Posted in: Physics | Date: 23/12/2017

Mass of the body is m Acceleration of the body is a Using Newton’s second law of motion, the force experienced by the body is given by the equation: F = ma Both m and a are constants. Hence, force will also be a constant. F = ma = Constant The velocity for uniformly accelerated motion is v = u + at = 0 + at = at Power is given by the relation: = Fv P = ma ∙ at P = ma^ 2 t As acceleration is constant, hence P∝t

• ## Question: A pebble of mass 0.05kg is thrown vertically upwards. Given the direction and ma...

Posted in: Physics | Date: 23/12/2017

0.5 N, in vertically downward direction, in all cases Acceleration due to gravity, irrespective of the direction of motion of an object, always acts downward. The gravitational force is the only force that acts on the pebble in all three cases. Its magnitude is given by Newton’s second law of motion as: F = m × a Where, F = Net force m = Mass of the pebble = 0.05 kg a = g = 10 m/s2 ∴F = 0.05 × 10 = 0.5 N The net force on the pebble in all three cases is 0.5 N and this force acts in the downward direction.

• ## Question: How much time does a fresher student need to get prepared for bankpo/clerk exam ...

Posted in: Bank PO | Date: 24/12/2017

If his/her maths base is good, then time required will lessen by a month or so. Overall, 6-7 months is required for a student to complete the syllabus and cover up the various portions of each subject. After that, continuous practice is required to adapt to the qstns asked, and devising a strategy to excel in the exam.

• ## Question: Help me to write expression for the average value of the a.c voltage V = Vo sin&...

Posted in: NEET | Date: 24/12/2017

A.C. voltage, V= V0 sin ωt As, t=π/ω=1/2.2π/ω=1/2T therefore, first half cycle (T/2). Hence, average value of AC voltage, Eav2V0π

• ## Question: Which is the best method of reducing current in an a.c circuit and why?

Posted in: Physics | Date: 24/12/2017

A.C. (Alternating Current) Circuits rely on an A.C. power source. Now, should you wish to reduce the current flowing in such a circuit, use an inductor or a capacitor since these devices would reduce the current flowing through the circuit while dissipating no power within themselves, thus causing no power loss!

• ## Question: Which device will you use to step up/ step down a.c voltage?

Posted in: AIPMT | Date: 24/12/2017

Transformers are used in AC

• ## Question: Power factor of an ac circuit is 0.5. What will be the phase difference between ...

Posted in: NEET | Date: 24/12/2017

cosϕ=0.5=1/2 => ϕ=60° Hence the phase difference is 60°

• ## Question: A vertical magnetic poles falls down through the plane of the magnetic meridian....

Posted in: Physics | Date: 24/12/2017

No emf is induced in the metallic case. When l and v are parallel, no emf is induced.

• ## Question: A choke coil and a bulb are connected inseries to a d.c source.The bulb shines b...

Posted in: Physics | Date: 24/12/2017

Intensity of the bulb decreases because there will be self induction effect when soft iron core is inserted.

• ## Question: Help me to draw the graphs showing the variation of reactance of (a) a capacitor...

Posted in: Physics | Date: 24/12/2017

Here, XC is the capacitive-reactance and is the frequency in an a.c circuit.

• ## Question: What minimum score is needed to secure a job in ssc cgl ?

Posted in: SSC Exams | Date: 25/12/2017

Tier 1 cutoff is around 130 for general. CBI SI post vacancies will be around 200 approx according to previous data. Expect CBI SI general vacancies (70 -80 ) to be filled under top 1000 ranks . (Again it depends on other top posts’ vacancies). Everything depend on Tier 2 exam level as it is the MAKE or BREAK stage . Tier 2 in SSC CGL 2016 was of fairly difficult level so we can take Tier 2 this will be of same level. So, as an approximation, you need to score around 490 out of 600 to be safe . Then around 65/100 in Tier 3 . Total around 555/700 to be safe for CBI as competition is increasing .

• ## Question: A soft-iron toroid is concentric with a long straight conductor carrying a direc...

Posted in: AIEEE | Date: 26/12/2017

Ans- 100...

• ## Question: Suppose that a shop has an equal number of LED bulbs of two different types. The...

Posted in: GATE Exam | Date: 26/12/2017

Suppose that a shop has an equal number of LED bulbs of two different types. ==> Therefore Probability of Taking Type 1 Bulb => 0.5 Probability of Taking Type 2 Bulb => 0.5 The probability of an LED bulb lasting more than 100 hours given that it is of Type 1 is 0.7, and given that it is of Type 2 is 0.4. Prob(100+ | Type1) => 0.7 Prob(100+| Type2) => 0.4 Prob(100+) => Prob(100+ | Type1) * Prob(Type1) + Prob(100+ | Type2) * Prob(Type2) = 0.7 * .5 + .4 * .5 = 0.55

• ## Question: A continuous-time sinusoid of frequency 33 Hz is multiplied with a periodic Dira...

Posted in: AIEEE | Date: 26/12/2017

Ans : 13 Hz. When 33 Hz and 46 Hz are multiplied with each other, we get signals of frequency 13 Hz and 79 Hz so on. Since we are passing the output through low pass filter, it allows only low frequency signals till it’s cut off frequency(23 Hz). So only 13 Hz is passed.

• ## Question: The second moment of a Poisson-distributed random variable is 2. The mean of the...

Posted in: GATE Exam | Date: 26/12/2017

The second moment of Poisson Distribution is: Here we have, λ2+λ=2λ2λ2. Solving we get, λ=−2,1λ21. The average number of events in an interval is designated λλ (lambda). Lambda is the event rate, also called the rate parameter. Since the number of events cannot be −ve... So the mean of random variable is 1

• ## Question: P, Q, R and S are working on a project. Q can finish the task in 25 days, workin...

Posted in: GATE Exam | Date: 26/12/2017

C-20:21. Q can finish the task in 25 days, working alone for 12 hours a day. What can we learn from this line?? That Q, in 25*12 hours can complete a work alone. That is, in his work in 1 hour is 1/25*12=1/300. R can finish the task in 50 days, working alone for 12 hours per day. Now, similarly, R's one hour work is 1/600. Now, Q has worked for 5 days of 12 hours(60 hours ) and R for 7 days of 18 hours( 126 hours). We finally know, how many hours both worked, and their capacity for a hour. ratio of work done by Q and R after 77 days from the start of the project= Work done by Q/Work done by R=(60* 1/300)/(126* 1/600)=20/21.

• ## Question: Michael lives 10 km away from where I live. Ahmed lives 5 km away and Susan live...

Posted in: GATE Exam | Date: 26/12/2017

C-6.02. michal ------------------10km----------------------------I LIVE AHMED---------5KM----------I LIVE SUSAN---------------7KM--------------------I LIVE SUSAN--ARUN--AHMED--------------------ILIVE SO ARUN IS BETWEEN 7 KM AND MORE THEN 5 KM SO HERE ANS IS LESS THEN 7 KM

• ## Question: In a huge pile of apples and oranges, both ripe and unripe mixed together, 15% a...

Posted in: GATE Exam | Date: 26/12/2017

Total fruits = 5692000 ={ Unripe(15%)→853800 Ripe(85%)→4838200 } ={ Unripe(15%){ Apples(45%)→384210 Orange→Don′t care } Ripe(85%){ Apples(34%)→1644988 Orange→Don′t care } } So, Total Apples = 384210 + 1644988 = 2029198-A

• ## Question: A Burglar’s car starts an acceleration of 2 m/s$$^2$$. A police vigilant p...

Posted in: Physics | Date: 26/12/2017

The distance after which the police catches the bburglar is 's' and time is 't'after the burglar car stated. Then, the time taken by police van to catch the burglar is 't−5'Now, applying second equation of motion to the burgar's car,s= ut 12at2s= 0×t 12 ×2×t2 (u=0 since car starts from rest)s= t2 −−−−(1)Applying the second equation of motin to the police car,s = ut 12at2s= 20×(t−5) 12 ×0×(t−5)2 (since it moves with uniform velocity a=0)s= 20t−100 −−−−− (2)since eq 1= eq 2t2 −20t 100 = 0(t−10)2 = 0 t −10 = 0 t=10 st−5 = 5 s....Therefore the police car over takes the burglar car after 5s it has reached the secene

• ## Question: A person travels equal distance with speeds of 3 km/hr, 4 km/hr and 5km/hr and t...

Posted in: Mathematics | Date: 26/12/2017

B-3 km. Explanation: Let the distance be 3x km, then, x/3+x/4+x/5=47/60....47x/60=4760....x=1. So total distance = 3*1 = 3 Km

• ## Question: The length of a rectangle is increased by 20% and its breadth decreased by 10%. ...

Posted in: Bank PO | Date: 26/12/2017

C- increase by 8%. Let length and width be xx and yy units respectively. Area=xyAreaxy After the length and width changes, the new area is Area=(x+x5)(y−y10)Areaxx5yy10 ⟹Area=6x5×9y10=54xy50=27xy25Area6x59y1054xy5027xy25 Percentage change in area=|27xy25−xy|xy×100=225×100=8

• ## Question: The man travelled a distance of 80 Km in 7 hours partly on foot with the speed o...

Posted in: Bank PO | Date: 26/12/2017

Ans-32 km. Suppose he travels on foot for x hours. Then, he travels on bicycle for ( 7 − x ) hours 8 x + 16 ( 7 − x ) = 80 ⇒ 8 x = 32 ⇒ x = 4 Distance travelled in foot = 8 × 4 = 32 km

• ## Question: A man invested RD of his capital at 7%, th of his capital at 8% and the remainde...

Posted in: Bank PO | Date: 26/12/2017

A-6600. Solution: Let initial amount that the man invests be A Let x be the capital => Profit on 1st investment + Profit on 2nd investment + Profit on 3rd investment => S.I. = P X R X T => Remainder of capital = 1 - 1/3 - 1/4 = 5/12x (x being the capital) => a*1/3 *7/100 + 1/4 *a * 8/100 + 5x/12*a* 10/100 = 561 Therefore, a = 6600

• ## Question: 4 men and 6 women finish a job in 8 days, while 3 men and 7 women finish it in 1...

Posted in: Mathematics | Date: 26/12/2017

Ans- 40 days... Let 1 man's 1 day's work = x and 1 woman's 1 day's work = y. Then, 4x + 6y = 1 and 3x + 7y = 1 . 8 10 Solving the two equations, we get: x = 11 , y = 1 400 400 1 woman's 1 day's work = 1 . 400 10 women's 1 day's work = 1 x 10 = 1 . 400 40 Hence, 10 women will complete the work in 40 days.

• ## Question: South is related to North-West in the same way as West is related to which of th...

Posted in: Bank Clerical | Date: 26/12/2017

E- none of these.... North-west direction is 1350 clockwise to the south direction. Similarly, North-east direction is 1350 clockwise to the south direction.

• ## Question: If Priti says, "Seema's father Amar is the only son of my father-in-law...

Posted in: Bank PO | Date: 26/12/2017

C- Grand daughter... As Amar is son of Mayank then Beena is grand daughter of Mayank....

• ## Question: Raju is standing in the garden and facing North-West. He turns 90° in clockw...

Posted in: Bank PO | Date: 26/12/2017

Ans-- South-east... The man initially faces in the direction OP. On moving 90° clockwise, he faces in the direction OX. On further moving 180° anticlockwise, he faces in the direction OY. Finally, on moving 90°anticlockwise, he faces in the direction OZ, which is South-east.

• ## Question: The average weight of 60 students in a class is 55 kg. Six of them, whose averag...

Posted in: Bank PO | Date: 26/12/2017

New Average weight = (60 * 55 - 40)/60 = 54.33 kg

• ## Question: Abhi invested an amount with Company X for two years at simple rate of interest ...

Posted in: Bank PO | Date: 26/12/2017

Let ‘y’ be the invested amount A.T.Q. 1.3y(1.12)2=81536 On Solving y=Rs.50,000/-

• ## Question: Some chocolates were distributed among 4 friends A, B, C and D such that the rat...

Posted in: Mathematics | Date: 26/12/2017

A=7x, C=9x, B=7x+29, D=9x+33 A.T.Q. 29 + 7x =15+9x ⇒ x = 7 ∴ D received 96 chocolates

• ## Question: Soumith purchased 10 calculators and 16 watches for Rs.56,100 and sold them so a...

Posted in: Bank PO | Date: 26/12/2017

CP of 10 calculators , 16 watches =Rs.56100/- CP of 15 calculators, 24 watches=1.5×56100=84150/- Profit=20% ∴S.P. of 15 calculators, 24 watches =1.2×84150 = Rs. 100,980/-

• ## Question: The difference between the length and the breadth of a rectangle is 6 m. The len...

Posted in: Bank PO | Date: 26/12/2017

Ans-- A- 96 .... Area of square= (side)2. => 729=(side)2. => Side=√729= 27... Now l=27. Diff.= 27-6 = 21= b. Now perimeter of rec. = 2(L+B). => 2(27+21). => 2(48). =>96....

• ## Question: Shashank bought 36 kg of sugar @ Rs.45 per kg and 24 kg of sugar @ Rs.42 per kg....

Posted in: Bank PO | Date: 26/12/2017

Price of 36 kg sugar @ Rs. 45 = 36 * 45 = Rs. 1620. Price of 24 kg sugar @ Rs. 42 = 24 * 42 = Rs. 1008. Total Cost Price = 1620 + 1008 = Rs. 2628. Total SP = 2628 + 20% of 2628 = Rs. 3153.6. Total Sugar = 36 = 24 = 60 kg. SP per kg = 3153.6 / 60 = Rs. 52.56.

• ## Question: An employer pays Rs.26 for each day a worker works and forfeits Rs.7 for each da...

Posted in: Mathematics | Date: 26/12/2017

His Per day pay = Rs. 26. Total pay employee got = Rs. 829. Total pay he gets if he did not remain idle a single day, = 26 *56 = Rs.1456. He Forfeits or fined = 1456 - 829 = Rs. 627. Per day he Forfeits Rs. 7. Means per idle day he looses = 26 +7 = Rs. 33. So, Total idle days = 627/33 = 19 days.

• ## Question: The number of students in institutes, A and B were in the ratio of 7 : 15 in 201...

Posted in: Bank PO | Date: 26/12/2017

Ratio of students in 2012 in institutes A and B, = 7 : 15. Let number of students in institute A in 2012 = 700. And Number of students in institutes B in 2012 = 1500. 25% increase in the number of students in 2013, Now, number of students in Institute A, = 700 + 25% of 700. = 875. Number of students in B in 2013 as 26% students increased in B, = 1500 + 26% of 1500 = 1890. Current Ratio of the students, = 875 /1890 = 25 : 54.

• ## Question: If a man runs at 6 kmph from his house he misses the train at the station by 8 m...

Posted in: Bank PO | Date: 26/12/2017

Home___________D Km____________Station. Let Distance of the station = D km. And actual time taken = t hours. Given, S1 = 6 kmph. Time taken to reach station with speed 6 kmph, = t + 8 min = [t +(8/60)] = t + (2/15)= (15t +2)/15 D = S1 *[t +(2/15)] = 6 *[t +(2/15)] -------- (1)[As, Distance = Speed *time] S2 = 10 kmph. Time taken to reach station with speed 10 kmph, = t - 7 min = t - (7/60) = (60t -7)/60 D = 10* [(60t - 7)/60] ----------------- (2) Comparing (1) and (2) 10* [(60t - 7)/60] = 6 *[t +(2/15)] (60t -7)/6 = 6 * [(15t +2)/15] (60t -7)/6 = (30t +4)/5 300t - 35 = 180t +24 t =15/4...

• ## Question: A, B and C entered into a partnership by investing Rs.64,000, Rs.52,000 and Rs.3...

Posted in: Mathematics | Date: 26/12/2017

E-20016. Required ratio of profit of A : B : C = 64 : 52 : 36 = 16 : 13 : 9 Now, let the share of profit of A be 16x, that of B be 13x and that of C be 9x The share of profit of A = 35584 16x = 35584 x = 35584/16 = Rs 2224 Hence the share of profit of C = 9 x 2224 = Rs 20016

• ## 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

C-48. Let the units digit be x and the tens digit be y Then, the number = 10y + x According to the question, x + y =12... (1) And 10x + y = 10y + x+36 9x - 9y =36 x - y = 4....(2) By solving (1) and (2), we get x = 8 Putting the value of x in (1), we get y = 4 Hence, the number = 10y + x = 10 x 4 + 8 = 48

• ## Question: A car covers the first 39 km of its journey in 45 minutes and the remaining 25 k...

Posted in: Mathematics | Date: 26/12/2017

D-48 km/hr. Average speed = Total distance/Total time (39 + 25)/(45 +35) minutes = 64/80 x 60 = 48 km/hr

• ## Question: 9 engines consume 24 metric tonnes of coal when each is working 8 hours daily. H...

Posted in: Bank Clerical | Date: 27/12/2017

Answer : 26 metric tonnes Description : As 9 engines consumes 24 metric tonnes of coal, when each working for 8 hours. Therefore, 1 engines consume in 1 hour = 24/(8*9) = 3 3 engines of former type = 4 engines of latter type. 6 engine of former type = 8 engine of latter type. Then, Coal required for 8 engines each running for 13 hours a day = 24*6*13/(8*9) = 26 metric tonne

• ## Question: The average age of husband, wife and their child 3 years ago was 27 years and th...

Posted in: Bank Clerical | Date: 27/12/2017

A-40. Explanation: Sum of the present ages of husband, wife and child = (27 x 3 + 3 x 3) years = 90 years. Sum of the present ages of wife and child (20 x 2 + 5 x 2) years = 50 years. Husband's present age = (90 - 50) years = 40 years.

• ## Question: The average weight of 8 person's increases by 2.5 kg when a new person comes...

Posted in: Bank Clerical | Date: 27/12/2017

Explanation: Total weight increased = (8 x 2.5) kg = 20 kg. Weight of new person = (65 + 20) kg = 85 kg.

• ## Question: A batsman makes a score of 87 runs in the 17th inning and thus increases his ave...

Posted in: Bank Clerical | Date: 27/12/2017

Let the average after 7th inning = x Then average after 16th inning = x - 3 16(x-3)+87 = 17x x = 87 - 48 = 39

• ## Question: Distance between two stations A and B is 778 km. A train covers the journey from...

Posted in: Bank Clerical | Date: 27/12/2017

If a car covers a certain distance at x kmph and an equal distance at y kmph. Then, average speed of the whole journey = 2xy/x+y kmph. By using the same formula, we can find out the average speed quickly. Average speed = 2×84×56/84+56=2×84×56/140=2×21×56/35 =2×3×56/5=33/65=67.2

• ## Question: The batting average for 40 innings of a cricket player is 50 runs. His highest s...

Posted in: Bank Clerical | Date: 27/12/2017

B-174. Explanation : Total runs scored by the player in 40 innings = 40 × 50 Total runs scored by the player in 38 innings after excluding two innings = 38 × 48 Sum of the scores of the excluded innings = 40 × 50 - 38 × 48 = 2000 - 1824 = 176 Given that the scores of the excluded innings differ by 172. Hence let's take the highest score as x + 172 and lowest score as x Now x + 172 + x = 176 => 2x = 4 => x =42 = 2 Highest score = x + 172 = 2 + 172 = 174

• ## Question: How to prepare for ssc chsl exam?

Posted in: SSC Exams | Date: 27/12/2017

for SSC CHSL first of all go to the syllabus and read it carefully. after that you have to select books that are essential for preparation.. there is a wide range of books in market .

• ## Question: Running at the same constant rate, 6 identical machines can produce a total of 2...

Posted in: Bank Clerical | Date: 27/12/2017

A-1800. 6 machines produce 270 bottles per minute; 1 machine produces 270/6=45 bottles per minute; 10 machines produce 45*10=450 bottles per minute; In 4 minutes 10 machines produce 450*4=1,800 bottles.

• ## Question: 39 persons can repair a road in 12 days, working 5 hours a day. In how many days...

Posted in: Bank Clerical | Date: 27/12/2017

D-13. Let the required number of days be x. Less persons, More days (Indirect Proportion) More working hours per day, Less days (Indirect Proportion) Persons 30 : 39 :: 12 : x Working hours/day 6 : 5 30 x 6 x x = 39 x 5 x 12 x = (39 x 5 x 12) (30 x 6) x = 13.

• ## Question: A certain industrial loom weaves 0.128 meters of cloth every second. Approximate...

Posted in: Bank Clerical | Date: 27/12/2017

D-195. Le the required time be x seconds. More metres, More time (Direct Proportion) 0.128 : 25 :: 1 : x 0.128x = 25 x 1 x = 25 = 25 x 1000 0.128 128 x = 195.31. Required time = 195 sec (approximately).

• ## 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: 27/12/2017

Let the height of the building x metres. Less lengthy shadow, Less in the height (Direct Proportion) 40.25 : 28.75 :: 17.5 : x 40.25 x x = 28.75 x 17.5 x = 28.75 x 17.5 40.25 x = 12.5

• ## Question: A contract is to be completed in 56 days if 104 persons work, each working at 8 ...

Posted in: Bank Clerical | Date: 27/12/2017

30*8*104*3/2 = 26*9*x => x = 160 additional workmen = 160-104=56 men

• ## Question:  x men working x hours per day can do xx units of a wor...

Posted in: Bank Clerical | Date: 27/12/2017

Ans-. Amount of work completed by 1 man in 1 day, working 1 hours a day = xx3=1x2Amount of work y men in y days, working y hours a day = y3×1x2=y3x2

• ## Question: 3 pumps, working 8 hours a day, can empty a tank in 2 days. How many hours a day...

Posted in: Bank Clerical | Date: 27/12/2017

B-12. 3 pumps take 16 hrs total (8 Hrs a day) If 1 pump will be working then, it will need 16*3=48 hrs 1 pump need 48 Hrs If I contribute 4 pumps then 48/4=12 hrs.

• ## Question: 9 examiners can examine a certain number of answer books in 12 days by working 5...

Posted in: Bank Clerical | Date: 27/12/2017

A-9. M1 = 9 D1 = 12 H1 = 5 W1 = 1 M2 = 4 D2 = 30 H2 = x W2 = 2 M1D1H1W1=M2D2H2W2⇒9×12×51=4×30×x2⇒9×12×5=2×30×x⇒3×12×5=2×10×x⇒3×6×5=10×x⇒3×3×5=5×x⇒x=3×3=9

• ## Question: A rope can make 70 rounds of the circumference of a cylinder whose radius of the...

Posted in: Bank Clerical | Date: 27/12/2017

A-49 rounds. Let the required number of rounds be x More radius, less rounds(Indirect proportion) Hence we can write as radius14:20}::x:70 ⇒14×70=20x⇒14×7=2x⇒x=7×7=49

• ## Question: A certain number of persons can finish a piece of work in 100 days. If there wer...

Posted in: Bank Clerical | Date: 27/12/2017

C-110. Explanation: Originally let there be x men. Less men, More days (Indirect Proportion) (x-10) : x :: 100 :110 10x= 1100 x= 110

• ## Question: On a scale of a map 0.6 cm represents 6.6km. If the distance between two points ...

Posted in: Bank Clerical | Date: 27/12/2017

A-885.5 km. Let the required actual distance be x km More scale distance, More actual distance(direct proportion) Hence we can write as scale distance.6:80.5}::6.6:x ⇒.6x=80.5×6.6⇒.1x=80.5×1.1⇒x=80.5×11=885.5

• ## Question: If the price of 357 apples is Rs.1517.25, what will be the approximate price of ...

Posted in: Bank Clerical | Date: 27/12/2017

price of 357 apples = Rs.1517.25price of 1 apple = Rs. 1517.25357price of 49 dozens apples = Rs.(49×12×1517.25357)≈Rs. 2500

• ## Question: A contract is to be completed in 56 days if 104 persons work, each working at 8 ...

Posted in: Bank Clerical | Date: 27/12/2017

Persons worked = 104 Number of hours each person worked per day = 8 Number of days they worked = 30 Work completed = 2/5 Remaining days = 56 - 30 = 26 Remaining Work to be completed = 1 - 2/5 = 3/5 Let the total number of persons who do the remaining work = x Number of hours each person needs to be work per day = 9 More days, less persons(indirect proportion) More hours, less persons(indirect proportion) More work, more persons(direct proportion) Hence we can write as DaysHoursWork30:268:935:25⎫⎭⎬⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪::x:104 ⇒30×8×35×104=26×9×25×x⇒x=30×8×35×10426×9×25=30×8×3×10426×9×2=30×8×104/26×3×2=30×8×4/3×2=5×8×4=160Number of additional persons required = 160 - 104 = 56

• ## Question: A certain industrial loom weaves 0.128 meters of cloth every second. Approximate...

Posted in: Bank Clerical | Date: 27/12/2017

Let the required time be x seconds. More metres, More time (Direct Proportion) 0.128 : 25 :: 1 : x 0.128x = 25 x 1 x = 25 = 25 x 1000 0.128 128 x = 195.31. Required time = 195 sec (approximately).

• ## Question: 3 pumps, working 8 hours a day, can empty a tank in 2 days. How many hours shoul...

Posted in: Bank Clerical | Date: 27/12/2017

Let the required number of working hours per day be x. More pumps, Less working hours per day (Indirect Proportion) Less days, More working hours per day (Indirect Proportion) Pumps 4 : 3 :: 8 : x Days 1 : 2 4 x 1 x x = 3 x 2 x 8 x = (3 x 2 x 8) (4) x = 12.

• ## Question: A wheel that has 6 cogs has meshed with a larger wheel of 14 cogs. If the smalle...

Posted in: Bank Clerical | Date: 27/12/2017

Let the required number of revolutions made by larger wheel be x. Then, More cogs, Less revolutions (Indirect Proportion) 14 : 6 :: 21 : x 14 x x = 6 x 21 x = 6 x 21/ 14 x = 9.

• ## Question: In a camp, there is a meal for 120 men or 200 children. If 150 children have tak...

Posted in: Bank Clerical | Date: 27/12/2017

B-30. There is a meal for 200 children. 150 children have taken the meal. Remaining meal is to be catered to 50 children. Now, 200 children 120 men. 50 children 120/200 x 50 = 30 men.

• ## Question: A boat running upstream takes 8 hours 48 minutes to cover a certain distance, wh...

Posted in: Bank Clerical | Date: 27/12/2017

Let the man's rate upstream be x kmph and that downstream be y kmph. Then, distance covered upstream in 8 hrs 48 min = Distance covered downstream in 4 hrs. x *8 4/5 = (y x 4) 44/5 x =4y y = 11/5x. Required ratio = (y + x)/2 : (y - x)/2 = (16x/5* 1/2) : (6x /5* 1/2) = 8/5: 3/5 = 8 : 3.

• ## Question: The speed of a boat in still water in 22 km/hr and the rate of current is 4 km/h...

Posted in: Bank Clerical | Date: 27/12/2017

Speed downstream = (22 + 4) = 26 kmph Time = 24 minutes = 24 60 hour = 2 5 hour Distance travelled = Time × speed = 2 5 ×26 = 10.4 km

• ## Question: Speed of a boat in standing water is 14 kmph and the speed of the stream is 1.2 ...

Posted in: Bank Clerical | Date: 27/12/2017

Speed downstream = (14 + 1.2) = 15.2 kmph Speed upstream = (14 - 1.2) = 12.8 kmph Total time taken = 4864/ 15.2 + 4864/ 12.8 = 320 + 380 = 700 hours

• ## Question: In an examination, a student's average marks were 63. If he had obtained 20 ...

Posted in: Bank Clerical | Date: 27/12/2017

Let the number of subjects = x Then, total marks he scored for all subjects = 63x If he had obtained 20 more marks for his Geography and 2 more marks for his history, his average would have been 65 => Total marks he would have scored for all subjects = 65x Now we can form the equation as 65x - 63x = additional marks of the student = 20 + 2 = 22 => 2x = 22 => x = 22/2 = 11

• ## Question: A family consists of two grandparents, two parents and three grandchildren. The ...

Posted in: Bank Clerical | Date: 27/12/2017

There are 2 grandparents of 67yrs (67*2) 2 parents of 35yrs (35*2) 3 grandchildren of 6yrs (6*3) average = sum of total ages/no.of persons 67 x 2 + 35 x 2 + 6 x 3 divided by 2 + 2 + 3 =31 5/7years

• ## Question: A library has an average of 510 visitors on Sundays and 240 on other days. What ...

Posted in: Bank Clerical | Date: 27/12/2017

In a 30 days month you will get 5 sundays if the 1st day is sunday. So 5 sundays x 510 = 2550 Remaining 25 days X 240 days =6000. So 2550 +6000= 8550/30 = 285.

• ## Question: In Kiran's opinion, his weight is greater than 65 kg but less than 72 kg. Hi...

Posted in: Bank Clerical | Date: 27/12/2017

D-67 kg. Let Kiran's weight = x. Then According to Kiran, 65 < x < 72 ----(equation 1) According to brother, 60 < x < 70 ----(equation 2) According to mother, x ≤ 68 ----(equation 3) Given that equation 1,equation 2 and equation 3 are correct. By combining these equations,we can write as 65

• ## Question: The average monthly income of A and B is Rs. 5050. The average monthly income of...

Posted in: Bank Clerical | Date: 27/12/2017

Let P, Q and R represent their respective monthly incomes. Then, we have: P + Q = (5050 x 2) = 10100 .... (i) Q + R = (6250 x 2) = 12500 .... (ii) P + R = (5200 x 2) = 10400 .... (iii) Adding (i), (ii) and (iii), we get: 2(P + Q + R) = 33000 or P + Q + R = 16500 .... (iv) Subtracting (ii) from (iv), we get P = 4000. P's monthly income = Rs. 4000.

• ## Question: The captain of a cricket team of 11 members is 26 years old and the wicket keepe...

Posted in: Bank Clerical | Date: 27/12/2017

A-23 years. Let the average age of the whole team by x years. 11x - (26 + 29) = 9(x -1) 11x - 9x = 46 2x = 46 x = 23. So, average age of the team is 23 years.

• ## Question: The average of 20 numbers is zero. Of them, How many of them may be greater than...

Posted in: Bank Clerical | Date: 27/12/2017

D-19. Average of 20 numbers = 0. Sum of 20 numbers (0 x 20) = 0. It is quite possible that 19 of these numbers may be positive and if their sum is a then 20th number is (-a).

• ## 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: 27/12/2017

Total sale for 5 months = Rs. (6435 + 6927 + 6855 + 7230 + 6562) = Rs. 34009. Required sale = Rs. [ (6500 x 6) - 34009 ] = Rs. (39000 - 34009) = Rs. 4991.

• ## Question: The diagonal of the floor of a rectangular room is 7$$\frac{1}{2}$$ fe...

Posted in: Bank Clerical | Date: 27/12/2017

Ans-27ft.

• ## Question: The ratio between the perimeter and the breadth of a rectangle is 5:1. If t...

Posted in: Bank Clerical | Date: 27/12/2017

Perimeter = Distance covered in 8 min. = (12000/60 x 8) m = 1600 m. Let length = 3x metres and breadth = 2x metres. Then, 2(3x + 2x) = 1600 or x = 160. Length = 480 m and Breadth = 320 m. Area = (480 x 320) m2 = 153600 m2.

• ## Question: The length of a rectangular plot is 20 meters more than its breadth. I...

Posted in: Bank Clerical | Date: 27/12/2017

Ans-60 m.

• ## Question: A room 5 m 44 cm long and 3 m 74 cm broad needs to...

Posted in: Bank Clerical | Date: 27/12/2017

A-176. Explanation: area of the room = 544 * 374 sq cm size of largest square tile = H.C.F of 544cm and 374cm= 34cm area of 1 tile = 34*34 sq cm no. of tiles required = (544*374) / (34 * 34) = 176

• ## Question: The length of a rectangle is twice its breadth. If its length is decreased by&nb...

Posted in: Bank Clerical | Date: 27/12/2017

C-40 cm. Explanation: Let breadth = x x cm Then, length = 2 x 2x cm Area = x × 2 x = 2 x 2 x2x2x2 sq.cm. New length = ( 2 x − 5 ) 2x5 cm New breadth = ( x + 5 ) x5 cm New area = ( 2 x − 5 ) ( x + 5 ) 2x5x5 sq.cm. Given that, new area = initial area + 75 75 sq.cm. ⇒ ( 2 x − 5 ) ( x + 5 ) = 2 x 2 + 75 ⇒ 2 x 2 + 10 x − 5 x − 25 = 2 x 2 + 75 ⇒ 5 x − 25 = 75 ⇒ 5 x = 75 + 25 = 100 ⇒ x = 100/ 5 = 20 cm Length = 2 x = 2 × 20 = 40

• ## Question: A large field of 700 hectares is divided into two parts. The difference of ...

Posted in: Bank PO | Date: 27/12/2017

Average of the two areas = 700 2 = 350 one-fifth of the average of the two areas = 350 5 = 70 350570 ⇒ Difference of the two areas = 70 70 Let area of the smaller part = x x hectares. Then, area of the larger part = x + 70 x70 hectares. x + ( x + 70 ) = 700 ⇒ 2 x = 630 ⇒ x = 315

• ## Question: A rectangular parking space is marked out by painting three of its sides. If the...

Posted in: Bank PO | Date: 27/12/2017

length = 9 feet breadth = 37 − 9/ 2 = 14 feet Area = 9 × 14 = 126 square feet

• ## Question: What is single touch method

Posted in: Physics | Date: 27/12/2017

When a bar magnet is brought near a magnetic material like iron, steel it gets attracted towards and sometimes gets lifted by the magnet if the material density is less. This is called Single touch method.

• ## Question: A red light 􀀢ashes 3 times per minute and a green light 􀀢ashes 5 times in ...

Posted in: CAT Exam | Date: 27/12/2017

D-60. The interval between red lights is 20 seconds and the interval between green lights is 12 seconds. Their LCM is 69 seconds. So the lights will flash together in 60 seconds

• ## Question: Anita had to do a mutiplication. Instead of taking 35 as one of the multipliers,...

Posted in: CAT Exam | Date: 27/12/2017

D-1590. Let the number that Anita wanted to multiply be 'X'. She was expected to find the value of 35X. Instead, she found the value of 53X. The difference between the value that she got (53X) and what she was expected to get (35X) is 540. i.e., 53X - 35X = 540 or (53 - 35) * X = 540 X = 30 Therefore, the correct product = 53 * 30 = 1590

• ## Question: The displacement of a particle moving in one dimension under the action of a con...

Posted in: AIEEE | Date: 27/12/2017

Explaination

• ## Question: In a car race, car A takes a time t less than car B and finishes the finishing p...

Posted in: Physics | Date: 27/12/2017

Ans--- √a1a2

• ## Question: What is coefficient of restitution ? Give its values for elastic collision, inel...

Posted in: Physics | Date: 27/12/2017

The coefficient of restitution (COR) is the ratio of the final to initial relative velocity between two objects after they collide. ... A perfectly inelastic collision has a coefficient of 0, but a 0 value does not have to be perfectly inelastic.

• ## Question: A train rounds an unbanked circular bend of radius 30 m at a speed of 54 km/h. T...

Posted in: Physics | Date: 27/12/2017

Ans-36.87°.

• ## Question: A force of 72 dyne is inclined to the horizontal at an angle of 60°. Find th...

Posted in: Physics | Date: 27/12/2017

Ans-4cms-2.

• ## Question: There are 500 cell phone users in the 1st Bank Office Building. It is known that...

Posted in: Bank PO | Date: 28/12/2017

Percentage= camera users/ total phone users*100. => 35/500*100. =>7%. So7% of users have camera phones..

• ## Question: Rita is trying to print her thesis paper on an inkjet printer that prints 4 page...

Posted in: Bank PO | Date: 28/12/2017

B-700 . 1 min= 4 pages. So 1400 pages = 350 min.... Now there are 2 copies so 350*2= 700 min....

• ## Question: Julie went shopping with Rs.250 in her purse. She purchased one sweater and a ja...

Posted in: CAT Exam | Date: 28/12/2017

A-160. Julie has 250 rs.. she purchased sweater for RS. 75. So 250-75= 175. But at the end shw had 15 rs left with her so,. 175-15= 160... So, she spend 160 on jacket..

• ## Question: In a car race, car A takes a time t less than car B and finishes the finishing p...

Posted in: Physics | Date: 28/12/2017

• ## Question: A train rounds an unbanked circular bend of radius 30 m at a speed of 54 km/h. T...

Posted in: AMITE | Date: 28/12/2017

Ans-36.87°.

• ## Question: The speed of sound waves depends on temperatre but speed of light waves does not...

Posted in: AMIE | Date: 28/12/2017

As we know that Sound is a mechanical wave and the speed of sound in air is given by : v = √(γRT/M) , which depends on temperature . But , light is an electromagnetic wave and the speed of light wave is given by : c = √(1/εoμo) , which is independent of temperature .

• ## Question: A force of 72 dyne is inclined to the horizontal at an angle of 60°. Find th...

Posted in: Physics | Date: 28/12/2017

Ans-4 cms.

• ## Question: How can I find resultant of two vectors when the two vectors (a) along the same ...

Posted in: Physics | Date: 28/12/2017

• ## Question: “The direction in which an object moves is given by the direction of veloc...

Posted in: Physics | Date: 28/12/2017

If a ball is thrown up, the direction of motion of the body is the same as the direction of its velocity whereas the acceleration due to gravity acts on it in the downward direction.Thus, the direction in which an object moves is given by the direction of velocity and not by the direction of acceleration.

• ## Question: An element with molar mass 63 g / mol forms a cubic unit cell with edge length o...

Posted in: AIEEE | Date: 28/12/2017

• ## Question: A metal crystallizes in a body centred cubic structure. If ‘a’ is th...

Posted in: AMIE | Date: 28/12/2017

Ans. r=√3/4 a

• ## Question: Tungsten crystallizes in body centred cubic unit cell. If the edge of the unit c...

Posted in: Chemistry | Date: 28/12/2017

Ams-137.04.

• ## Question: The limiting molar conductivity of ‘B’ increases 1.5 times while tha...

Posted in: Chemistry | Date: 28/12/2017

The strong electrolyte is B. Since strong electrolyte are completely or near completely dissociated with high concentrations. So dilution has only a small effect on small electrolytes molar conductivity. It is opposite for a which is aweal electrolytes increasing strongly molar conductivity when diluting.

• ## Question: A coordination compound with molecular formula CrCl$$_3$$. 4H$$_2$$O precipitate...

Posted in: Chemistry | Date: 28/12/2017

The structural formula of the other compound is [Cr(H2O)4Cl2]Cl⋅2H2O.

• ## Question: In the process of wine making, ripened grapes are crushed so that sugar and enzy...

Posted in: Chemistry | Date: 28/12/2017

If anaerobic condition are not maintained then enzymes cannot act and hence it cannot be mix properly...

• ## Question: A can do a piece of work in 6days and B can do in 12 days. Together they can com...

Posted in: Bank PO | Date: 28/12/2017

A can do work in 6 days = 1/6. B can do work in 12 days= 1/12. They can complete work together= 1/6+1/12. => 3/12 => 1/4... So they can complete the work in 4 days....

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

Posted in: Bank Clerical | Date: 28/12/2017

D-44. If age of the teacher was 21, average would not have changed. Since average increased by 1 1, Age of the teacher = 21 + 23 × 1 = 44

• ## Question: A man is 24 years older than his son. In two years, his age will be twice t...

Posted in: Bank Clerical | Date: 28/12/2017

B-22 years. Let the son's present age be x years. Then, man's present age = (x + 24) years. (x + 24) + 2 = 2(x + 2) x + 26 = 2x + 4 x = 22.

• ## Question: A man's age is 125% of what it was 10 years ago, but 83$$\fra... Posted in: Bank Clerical | Date: 28/12/2017 ### Answer: Ans- 50 years. Let the age before 10 years = x x. Then, 125 x 100 = x + 10 ⇒ 125 x = 100 x + 1000 ⇒ x = 1000 25 = 40 Present age = x + 10 = 40 + 10 = 50 • ## Question: Study the following information and answer the following questions. Eight peo... Posted in: Bank PO | Date: 28/12/2017 ### Answer: Ans--- 1) G is sitting second to the right of E... 2) K is professor.... 3) Third to the right... • ## Question: Read the given information carefully and answer the given questions. Each of ... Posted in: Bank PO | Date: 28/12/2017 ### Answer: Ans---1) 36 N > J > K > M > I > L K=31 L=12 From the question , J Possibly handles only 36. Because K handled 31 projects so that J must be greater than 31. So answer is 36. Ans---2) (I+K) = 33+L. => 33+12. => (I+K)= 45. Now K =31 so I = 45-31 = 14.... • ## Question: The respective ratio of radii of two right circular cylinders (A and B) is 3 : 2... Posted in: Bank Clerical | Date: 28/12/2017 ### Answer: B-4:7. 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 • ## Question: A is thrice as efficient as B. A started working and after 4 days he was replace... Posted in: Bank PO | Date: 28/12/2017 ### Answer: D-36 days. • ## Question: In a bag, there are 6 red balls and 9 green balls. Two balls are drawn at random... Posted in: Bank PO | Date: 28/12/2017 ### Answer: C-23/35. 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 • ## Question: A vessel contains a mixture of milk and water in the respective ratio of 10 : 3.... Posted in: Bank PO | Date: 28/12/2017 ### Answer: D-156. • ## Question: The inductance of a coil will increase under all the following conditions except Posted in: Physics | Date: 29/12/2017 ### Answer: A- The inductance of a coil will increase under all the following conditions except when more length for the same number of turns is provided.... • ## Question: Which of the following circuit element stores energy in the electromagnetic fiel... Posted in: Physics | Date: 29/12/2017 ### Answer: A- inductance. An inductor stores the kinectic energy of moving electron in form of magnetic field. • ## Question: As per Faraday's laws of electromagnetic induction, an e.m.f. is induced in ... Posted in: Physics | Date: 29/12/2017 ### Answer: C-As per Faraday's laws of electromagnetic induction, an e.m.f. is induced in a conductor whenever it cuts magnetic flux... • ## Question: The property of coil by which a counter e.m.f. is induced in it when the current... Posted in: Physics | Date: 29/12/2017 ### Answer: A-The property of coil by which a counter e.m.f. is induced in it when the current through the coil changes is known as self-inductance... • ## Question: The cost price of item B is Rs. 150/- more than the cost price of item A. Item A... Posted in: Bank PO | Date: 29/12/2017 ### Answer: A- Rs. 450/-. Let CPa and CPb be the cost prices of the items A and B Given that CPb = CPa + 150 Also given that item A was sold at 1.1 CPa . Item B was sold at 0.8 CPb or 0.8 (CPa + 150) By the question, 1.1 CPa / (0.8 CPa +120) = 11/12 This gives 13.2 CPa = 8.8 CPa + 1320, Solving we get CPa = 300 Therefore CPb = 300 + 150 = 450 • ## Question: The cost price of item B is Rs. 150/- more than the cost price of item A. Item A... Posted in: Bank PO | Date: 29/12/2017 ### Answer: Let CPa and CPb be the cost prices of the items A and B Given that CPb = CPa + 150 Also given that item A was sold at 1.1 CPa . Item B was sold at 0.8 CPb or 0.8 (CPa + 150) By the question, 1.1 CPa / (0.8 CPa +120) = 11/12 This gives 13.2 CPa = 8.8 CPa + 1320, Solving we get CPa = 300 Therefore CPb = 300 + 150 = 450 • ## Question: What is H’s position with respect to B? Posted in: Bank PO | Date: 29/12/2017 ### Answer: A- 5th to the right. • ## Question: In which of the following combinations is the 1st person sitting between the 2nd... Posted in: Bank PO | Date: 29/12/2017 ### Answer: A-GCD • ## Question: Total sales of branch B6 for both the years is what percent of the total sales o... Posted in: Bank PO | Date: 29/12/2017 ### Answer: C-73.17%. Required percentage = (70 + 80) x 100 % (95 + 110) = 150 x 100 % 205 = 73.17%. • ## Question: What is the ratio of the total sales of branch B2 for both years to the total sa... Posted in: Bank PO | Date: 29/12/2017 ### Answer: D-7:9. Required ratio = (75 + 65)/(85+65) = 140 /180 = 7/9. • ## Question: A camel pursue an elephant and takes 5 leaps for every 7 leaps of the elephant, ... Posted in: Bank PO | Date: 29/12/2017 ### Answer: C-25:21. Solutions: Ratio of speed of camel and elephant = 5/3 : 7/5 = 5/3 X 15 : 7/5 X 15 = 25:21 • ## Question: Which of the following is a pair of co-primes? Posted in: Bank PO | Date: 29/12/2017 ### Answer: B- (18,25) • ## Question: A Students was asked to find the arithmetic mean of the numbers 3, 11, 7, 9, 15,... Posted in: Bank PO | Date: 29/12/2017 ### Answer: B-7. (3 + 11 + 7 + 9 + 15 + 13 + 8 + 19 + 17 + 21 + 14 + x) / 12 = 12. or 137 + x = 144 or x = 144 - 137 = 7. • ## Question: Which one of the following is the common factor of (47\(^{43}$$ + 43$$^{43}$$ ) ...

Posted in: Bank PO | Date: 29/12/2017

B-(47+43). As we know an−bn=(a−b)(an−1+an−2b+…+abn−2+bn−1) anbnaban1an2babn2bn1 . Now, if n n is odd then bn=−(−b)n bnbn , so using the above an+bn=an−(−b)n=(a−(−b))(an−1+an−2(−b)+…+a(−b)n−2+(−b)n−1)= anbnanbnaban1an2babn2bn1 =(a+b)(an−1−an−2b+…−abn−2+bn−1) aban1an2babn2bn1 (4743+4343)=(47+43)(4742−474143+…−47∗4341+4342) 47434343474347424741434743414342 (4747+4347)=(47+43)(4746−474543+…−47∗4345+4346) Common is (47+43)

• ## Question: An astronomical telescope is adjusted to form the final image at infinity. The s...

Posted in: Physics | Date: 29/12/2017

Ans-75 cm

• ## Question: The focal length of a concave lens is 20 cm. The focal length of a convex lens i...

Posted in: Physics | Date: 29/12/2017

Focal length of concave lens = -20 cm = -20/100 m power = P₁ = 1/-20/ 100 = -5 D focal length of convex lens = +25 cm = 25/100 m power = P₂ = 1/25/100 = 4 D So net power = P = P₁ + P₂ = -5D + 4D = -1 D (implies combination behave as concave lens).

• ## Question: What are coarse grain crops and what re the difference between jute and cotton a...

Posted in: Geography | Date: 30/12/2017

Coarse grains generally refers to cereal grains other than wheat and rice — in the OECD countries, those used primarily for animal feed or brewing. The climatic condition for Jute Cultivation is mentioned below : Temperature: 25°C is ideal for jute cultivation. Rainfall: 150 cm to 200 cm rainfall is essential for jute cultivation. Moisture in the wind is necessary. Soil: New alluvial or loamy soil or river basin is ideal for jute cultivation. Land: Plain land or gentle slope or low land is ideal for jute cultivation. But huge number of cheap labor is required along with irrigation facilities. HYV Seeds like Basudev, Sobajsora etc., plenty of fertilizer are required. The ideal conditions for the production of cotton are: Climate: Cotton grows well in warm and moist climate where summer is long and where there is salinity in the soil. Temperature: Cotton grown well in a temperature of 24°C. But cotton bursts out, high temperature is injurious. Rainfall: 60-100 cm rainfall is essential for the cultivation of cotton. But rainfall after the cotton comes out of the cocoon in injurious. Soil: Loamy soil mixed with lime and potash is good for cotton. Cotton grows well in Black Cotton Soil which is sticky in nature and has water retentive capacity. Land: Plain lands or gentle slope lands are good for cotton production. Drainage is necessary for the cultivation of cotton.

• ## Question: Find the area of a square whose diagonal is 12cm

Posted in: Bank PO | Date: 30/12/2017

Area = 1/2 * diagonal(square) Area = 1/2 *12^2 Area = 1/2 * 144 Area = 72 cm^2

• ## Question: Complete the series: 2, 12, 36, 80, ....

Posted in: Bank PO | Date: 30/12/2017

Ans-150. As 2 = 1x1x1 + 1x1 12 = 2x2x2 + 2x2 36 = 3x3x3 + 3x3 so on ... so, ans = 5x5x5 + 5x5 = 125 + 25 = 150

• ## Question: Two capacitors have capacity 15μF when connected in parallel and 10/3 μF w...

Posted in: Physics | Date: 30/12/2017

Ans-12 πF, 4πF...

• ## Question: Drive the expression for the electric field at distance r due to an infinite wir...

Posted in: AIEEE | Date: 30/12/2017

Potential of any point a with respect to any other point b,..

• ## Question: The energy of an electron in the first Bohr orbit of an atom is -27.2 eV. What w...

Posted in: Physics | Date: 30/12/2017

Ans- -6.8 eV. The energy of an electron in a Bohr atom is expressed as where, k = constant, Z = atomic number, N = orbit number E_n = - 〖kZ〗^2/n^2 = - 27.6eV for H (n = 1) When n = 2, E2 = E_2 = (- 27.6)/2^2 eV = - 6.80 eV (n can have only integral value 1, 2, 3,……. ∞)

• ## Question: How to calculate the critical angle for glass and water pair?

Posted in: Physics | Date: 30/12/2017

Ans-- 1.08°. Refractive index of air w.r.to glass, gηa = 1.50 Refractive index of air w.r.to water, wηa = 133 Therefore, aηg x gηw x wηa= 1 1/1.50 xgηw 1.33 = 1 gηw = 1.50/ 1.33 = 1.13 gηw = 1/sin C Sin C = l/gηw = 1/1.13 = 0.88 C = 1.08° , is the critical angle.

• ## Question: A 0.4 m long straight conductor is moved in a magnetic field of induction 0.9 Wb...

Posted in: Physics | Date: 30/12/2017

Ans-- 2.52V. V = BvL = 0.9 x 7 x 0.4 = 2.52V

• ## Question: What is the differentiate between heating effect produced by Peltier and Joule e...

Posted in: Physics | Date: 30/12/2017

Peltier’s Effect 1. It takes place only at the junction. 2. Heat is evolved or absorbed. 3. It is a reversible process. 4. It depends on the direction of current 5. Heat is evolved or absorbed is proportional to the current. 6. Amount of heat evolved or absorbed depends on the nature of the metals and temperature of the conductor. Joule’s Effect 1. It takes place throughout the conductor. 2. Heat is always produced. 3. It is an irreversible process. 4. It is independent of the direction of the current. 5. Heat produced is proportional to the square of the current. 6. Amount of heat produced depends on the resistance of the conductor.

• ## Question: How does the energy of a parallel plate capacitor change when the area of plates...

Posted in: Physics | Date: 30/12/2017

The energy of a parallel plate capacitor increase when the area of plates is doubled...

• ## Question: When processing flower nectar into honeybees' extract, a considerable amount of ...

Posted in: GRE | Date: 30/12/2017

Ans- 1.7 kgs. Flower-nectar contains 50% of non-water part. In honey this non-water part constitutes 85% (100-15). Therefore 0.5 X Amount of flower-nectar = 0.85 X Amount of honey = 0.85 X 1 kg Therefore amount of flower-nectar needed $= ({0.85/0.5} × 1)kg =$1.7 kgs

• ## Question: In an election contested by two parties, Party D secured 12% of the total votes ...

Posted in: GRE | Date: 30/12/2017

Ans-36,000. Let the percentage of the total votes secured by Party D be x% Therefore, the percentage of total votes secured by Party R = (x - 12)% As there are only two parties contesting in the election, the sum of the votes secured by the two parties should add up to 100% i.e., x + x - 12 = 100 2x - 12 = 100 or 2x = 112 or x = 56%. If Party D got 56% of the total votes, then Party R would have got (56 - 12) = 44% of the total votes. 44% of the total votes = 132,000 i.e., 4410044100 * T = 132,000 => T = 132000∗1004413200010044 = 300,000 votes. The margin by which Party R lost the election = 12% of the total votes = 12% of 300,000 = 36,000.

• ## Question: If the price of petrol increases by 25% and Raj intends to spend only an additio...

Posted in: GRE | Date: 30/12/2017

Ans-- 8%. let 1 lt cost 1 rupees now again 1 lt cost is 125/115 increase=125/115-1; %reduce=inc*100/inc cost=(2*23*100)/(23*25) =8%

• ## Question: Michael lives 10 km away from where I live. Ahmed lives 5 km away and Susan live...

Posted in: CAT Exam | Date: 30/12/2017

Ans-6.02 km. ---------------------- 5 km ahmed i live --------------------------------------------------------------------------------10 km michael ----------------------------------------7km susan question say that Arun is father who away from Ahmed and closer to susan means value lies greater than 5 and less than 7......only one value which is 6.02

• ## Question: A man can hit a target once in 4 shots. If he fires 4 shots in succession, what ...

Posted in: GRE | Date: 30/12/2017

P(hitting one shot)=4C1*(1/4)*(3/4)^3=108/256 P(hitting two shots)=4C2*(1/4)^2*(3/4)^2=54/256 P(hitting three shots)=4C3*(1/4)^3*(3/4)=12/256 P(hitting all 4 shots)=4C4*(1/4)^4=1/256 So, P(hitting)= 108/256+54/256+12/256+1/256= 175/256

• ## Question: A survey of n people in the town of Eros found that 50% of them prefer Brand A. ...

Posted in: GRE | Date: 30/12/2017

a weighted average question. Since the given average of 50% and 60% is 55% (right in the middle), it means the number of people surveyed in Eros (n) is same as the number of people surveyed in Angie. So n = 100 Total = 100 + 100 = 200

• ## Question: There are 750 male and female participants in a meeting. Half the female partici...

Posted in: GRE | Date: 30/12/2017

female = x Male = 750-x x/2 + 750-x/4 = 1/3* (750)= 250 x= 250 x/2 = 125

• ## Question: In a multi-voting system, voters can vote for more than one candidate. Two candi...

Posted in: GRE | Date: 31/12/2017

by double matrix chart... A not A B not B Total for A - 100 For A and B both - 50 For A alone 50 For neither is 0. we then have that 150 people not voted for A, and voted for B only.

• ## Question: In a factory, there are workers, executives and clerks. 59% of the employees are...

Posted in: GRE | Date: 31/12/2017

59% of the employees E are workers. Since the factory consists of only workers, executives, and clerks, the remaining 100 – 59 = 41% of the employees must include only executives and clerks. Since we are given that the number of executives is 460 and the number of clerks is 360, which sum to 460 + 360 = 820, we have the equation (41/100)E = 820, or E = 100/41× 820 = 2000.

• ## Question: If p and q are both positive integers such that p/9 + q/10 is also an integer, t...

Posted in: GRE | Date: 31/12/2017

C-9. Let kk be an integer such that p9+q10=kp9q10k. Since all three numbers pp, qq, and kk are integers, among the given options, the only case could be: integer (p9)p9 + integer (q10)q10 = integer (k)k The only value that fits the condition is (C). So, Ans - C.

• ## Question: If 42.42 = k(14 + m/50), where k and m are positive integers and m < 50, then wh...

Posted in: GRE | Date: 31/12/2017

42.42 = 14K + Km/50...we can rewrite the number as follows: 42+ 0.42= 14K + Km/50........Since K is integer, then 42=14K..........K=3 0.42=Km/50......42/100=3m/50......m=7 k+m=3+7=10

• ## Question: The remainder when the positive integer m is divided by n is r. What is the rema...

Posted in: GRE | Date: 31/12/2017

Plug in some numebrs and check - m = 5 n = 3 r = 2 What is the remainder when 2m is divided by 2n ? 2m = 10 2n = 6 So, Remainder when 2m is divided by 2n is = 4 2r = 4 Thus, answer must be 2r

• ## Question: (The average of five consecutive integers starting from m) – (the average of s...

Posted in: GRE | Date: 31/12/2017

Using number properties: the average value of an even list of consecutive numbers will be the middle number. list of numbers: m m+1 m+2 m+3 m+4 average given in question stem: n average as per the number properties rule: m+2 Therefore m+2 = n New list: " 9 consecutive integers that start with (m + 2)" ... since m+2 = n: n n+1 n+2 n+3 n+4 n+5 n+6 n+7 n+8 Average (using the same number properties rule): n n+1 n+2 n+3 n+4 n+5 n+6 n+7 n+8

• ## Question: By how much is the greatest of five consecutive even integers greater than the s...

Posted in: GRE | Date: 31/12/2017

smallest of five consecutive even integer = x greatest of five consecutive even integers = x+8 greatest of five consecutive even integers - smallest of five consecutive even integer = x + 8 - x = 8

• ## Question: Find the smallest number that leaves a remainder of 4 on division by 5, 5 on div...

Posted in: GRE | Date: 31/12/2017

LCM (5, 6, 7, 8, 9) - 1 = 2519.

• ## Question: A number is selected at random from first thirty natural numbers. What is the ch...

Posted in: GRE | Date: 31/12/2017

Number of Multiples of 3 from 1 through 30 = 30/3 = 10 Number of Multiples of 13 from 1 through 30 = 30/13 = 2 Number of Multiples of 3 and 13 both from 1 through 30 = Number of Multiples of 13*3(=39) = 0 Total favourable cases = 10 + 2 - 0 = 12 Probability = 12 / 30 = 2/5

• ## Question: An anti aircraft gun can fire four shots at a time. If the probabilities of the ...

Posted in: GRE | Date: 31/12/2017

P(zero shots hit plane) = P(1st shot misses AND 2nd shot misses AND 3rd shot misses AND 4th shot misses) = P(1st shot misses) x P(2nd shot misses) x P(3rd shot misses) x P(4th shot misses) = 0.3 x 0.4 x 0.5 x 0.6 = 3/10 x 4/10 x 5/10 x 6/10 = 360/10000 = 0.036 So....... P(at least 1 shot hits plane) = 1 - P(zero shots hit plane) = 1 - 0.036 = 0.964

• ## Question: When 4 dice are rolled simultaneously, what is the probability that the same num...

Posted in: GRE | Date: 31/12/2017

The total number of elementary events associated to the random experiments of throwing four dice simultaneously is: = 6*6*6*6=64 n(S) = 64 Let X be the event that all dice show the same face. X = { (1,1,1,1,), (2,2,2,2), (3,3,3,3), (4,4,4,4), (5,5,5,5), (6,6,6,6)} n(X) = 6 Hence required probability = n(X)/ n(S) = 6/ 64*4 = 1/ 216

• ## Question: When two dice are thrown simultaneously, what is the probability that the sum of...

Posted in: GRE | Date: 31/12/2017

11/12 36 possible outcomes P(11, that is either [5,6] or [6,5]) = 2/36. P(12, that is [6,6]) = 1/12 hence P(11 or 12) = P(sum>= 11) = 3/36 = 1/12 P(sum=11) = 1 - 1/12 = 11/12

• ## Question: Two squares are chosen at random on a chessboard. What is the probability that t...

Posted in: GRE | Date: 31/12/2017

In a chessboard the 4 squares at corners share a side only with 2 squares. If the first square is at corner, then the other square must be from those 2. out of four one square can be chosen in 4c1 ways; hence total no. of ways = 4*2=8 the remaining 24 squares of sidemost rows share a side with 3 squares; hence total no. of ways = 24*3=72 other 36 squares share a side with 4 squares; thats y total no. of ways= 36*4=144 144+72+8=224 are the no. of ways in which 2 squares sharin a side can be selected. total no of ways of selecting 2 squares out of 64 squares are= 64c2 the required probability= 224/(64c2)= 1/9

• ## Question: A man bets on number 16 on a roulette wheel 14 times and losses each time. On th...

Posted in: GRE | Date: 31/12/2017

Each of the span is an independent event and the outcome of the 15 th span will not depend on the outcome of the earlier spans. So, Either 35:1

• ## Question: What is the probability that a two digit number selected at random will be a mul...

Posted in: GRE | Date: 31/12/2017

There are a total of 90 two digit numbers. Every third number will be divisible by '3'. Therefore, there are 30 of those numbers that are divisible by '3'. Of these 30 numbers, the numbers that are divisible by '5' are those that are multiples of '15'. i.e. numbers that are divisible by both '3' and '5'. There are 6 such numbers -- $15, 30, 45, 60, 75$ and $90$. We need to find out numbers that are divisible by '3' and not by '5', which will be: $30 - 6 = 24$. 24 out of the 90 numbers are divisible by '3' and not by '5'. The required probability is therefore, $24/90$ = 4/15

• ## Question: What is the probability of getting at least one six in a single throw of three u...

Posted in: GRE | Date: 31/12/2017

P(getting a 6) = 1/6 P(not getting a 6 on one throw) = 5/6 P (not getting a 6 on three throws) = 5/6*5/6*5/6 = 125/216 P(getting at least a 6) = 1-125/216= 91/216

• ## Question: Anita had to do a multiplication. Instead of taking 35 as one of the multipliers...

Posted in: CAT Exam | Date: 31/12/2017

35X=y ; 53X=y 540; 53X=35X 540; 18X=540; X=540/18=30; 53x30=1590

• ## Question: Galvanization is applying of coating of

Posted in: Chemistry | Date: 31/12/2017

Galvanizing means coating Zinc on iron surface as in steel pipes for use domestic in plumbing before the advent of plastic water pipes...

• ## Question: Half-lives of two radioactive elements A and B are 20 minutes and 40 minutes, re...

Posted in: Physics | Date: 31/12/2017

80 minutes = 4 half-lives of A = 2 half-lives of B Let the initial number of nuclei in each sample be N NANA after 80 minutes =N/2^4 => Number of A nuclides decayed =15/16N NBNB after 80 minutes =N/2^4 => Number of B nuclides decayed =3/4N Required ratio =15/16/3/4 =5/4

• ## Question: An observer looks at a distant tree of height 10 m with a telescope of magnifyin...

Posted in: Physics | Date: 31/12/2017

Telescope creates a focused image of a distant object, so that the object looks nearer. Magnifying power of telescope, M = 20, implies that the tree appears 20 times nearer.

• ## Question: The distance of the point (1, –5, 9) from the plane x – y + z = 5 measured a...

Posted in: Advanced Maths | Date: 31/12/2017

Equation of line parallel to x = y = z through (1, –5, 9) is x -1/1= y- 5/1 = z -9/ 1 = a Now if If P(a+ 1, a– 5, a+ 9) be point of intesection of line and plane then a+1 + a-5 + a+9 =5. Solving this a=-10 which means Coordinates point are (–9, –15, –1) and hence distance is 10 * root(3)

• ## Question: A wire of length 2 units is cut into two parts which are bent respectively to fo...

Posted in: Advanced Maths | Date: 31/12/2017

Let length of two parts be ‘a’ and ‘2 - a’ As per condition given, we write a=4xand2−a=2πra4xand2a2πr x=a4xa4 and r=2−a2πr2a2π ∴A(square)=(a4)2=a216Asquarea42a216 and A(circle)=π[(2−a)2π]2=π(4+a2−4a)4π2Acircleπ2a2π2π4a24a4π2 =(a2−4a+4)4πa24a44π f(a)=a216+a2−4a+44πfaa216a24a44π ∴f(a)=a2π+4a2−16a+1616πfaa2π4a216a1616π f′(a)=116πfa116π[2aπ+8a−16]2aπ8a16 f′(a)=0=>2aπ+8a−16=0fa02aπ8a160 => 2aπ+8a=162aπ8a16 x=a4=2π+4xa42π4 and r=2−a2πr2a2π =2−8π+42π28π42π =2π+8−82π(π+4)2π882ππ4 =1π+41π4 x=2π+4x2π4 and r=1π+4r1π4 x=2r

• ## Question: How will the force between two equal charges change if the charges are halved an...

Posted in: Physics | Date: 31/12/2017

By Coulomb’s Law, Force is inversely proportional to square of distance between two charged particles. So if distance increases 2 times, force reduces 4 times.

• ## Question: On the basis of Huygen’s wave theory, prove Snell’s law of refractio...

Posted in: AIEEE | Date: 31/12/2017

On the basis of Huygen's wave theory, the laws of refraction Given : AEB is the incident wave front and DGC be the refracted wavefront. BC = V1t V1 = velocity of light in medium 1. AD = V2t V2 = velocity of light in medium 2.

• ## Question: In the circuit shown in Figure  below, E is a battery of emf 6 V and intern...

Posted in: AIEEE | Date: 31/12/2017

Ans-- The reading on Ammeter is 0.5 A

• ## Question: Write a balanced nuclear reaction showing emission of a β-particle by ...

Posted in: Physics | Date: 31/12/2017

234Th90 → 234Pa91 + 0e−1 + energy

• ## Question: Threshold frequency of a certain metal for photo-electric emission is \(5 \times...

Posted in: Physics | Date: 31/12/2017

Energy of photon = kinetic energy of photon electron + threshold frequency

• ## Question: What condition must be satisfied by two thin lenses kept in contact so that they...

Posted in: AMIE | Date: 31/12/2017

Condition for achromatic doublet of two lens:. w/f + w/f' =0 w+w' are the dispersive power of two lens, f + f' are the respective focal length.

• ## Question: In a moving coil galvanometer, what is meant by a radial magnetic field?

Posted in: Physics | Date: 31/12/2017

When the magnet are grounded concave, the fields lines then pass radially by across the pole pieces such a field is known as radial field.

• ## Question: Write an expression of magnetic flux density ‘B’ at a point in end-o...

Posted in: Physics | Date: 31/12/2017

Magnetic flux density at the axial position::: |B axial| = myu/ 4π =2|M|r/(r^2-l^2)^2

• ## Question: Binding energy of a nucleus is of the order of:

Posted in: Physics | Date: 31/12/2017

C-Mega electron volt(MeV)

• ## Question: Help me to solve this question . White light is passed through sodium vapour&nb...

Posted in: Physics | Date: 31/12/2017

C-Band spectrum

• ## 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: 01/01/2018

B-7.5 m. Length of the carpet = (total cost)/(Rate /m) = (8100)/(46) = 180 m Area of the room = Area of the carpet = (180 * 75/100) = 135 sq m Hence, Breadth of the room = (area)/(length) = 135/18 = 7.5 m

• ## Question: An agent gets a commission of 2.5% on the sales of cloth. If on a certain day, h...

Posted in: Bank PO | Date: 01/01/2018

B- Rs. 500. Let the total sale be Rs. x. Then, 2.5%. of x = 12.50 (25/100 * 1/100 * x) = 125/10 x = 500.

• ## Question: A lent Rs. 5000 to B for 2 years and Rs. 3000 to C for 4 years on simple interes...

Posted in: Bank PO | Date: 01/01/2018

D-10%. Let the rate be R% p.a. Then, 5000 x R x 2 + 3000 x R x 4 = 2200. 100 100 100R + 120R = 2200 R = 2200 = 10. 220 Rate = 10%.

• ## Question: Two pipes A and B can fill a tank in 20 and 30 minutes respectively. If both the...

Posted in: Bank PO | Date: 01/01/2018

Part filled by A in 1 min = 1 . 20 Part filled by B in 1 min = 1 . 30 Part filled by (A + B) in 1 min = 1 + 1 = 1 . 20 30 12 Both pipes can fill the tank in 12 minutes.

• ## Question: On 6th March 2005 Monday falls. What was the day of the week on 6th March 2004?

Posted in: Bank PO | Date: 01/01/2018

A- Sunday. The year 2004 is a leap year. So, it has 2 odd days. But, Feb 2004 not included because we are calculating from March 2004 to March 2005. So it has 1 odd day only. The day on 6th March, 2005 will be 1 day beyond the day on 6th March, 2004. Given that, 6th March, 2005 is Monday. 6th March, 2004 is Sunday (1 day before to 6th March, 2005).

• ## Question: The ratio between the total expenditure on taxes for all the years and the total...

Posted in: Bank PO | Date: 01/01/2018

B-10:13. Required Ratio will be (83+108+74+88+98/98+112+101+133+142)=(451/586)=1/1.3=10:13

• ## Question: The total expenditure of the company over these items during the year 2000 is?

Posted in: Bank PO | Date: 01/01/2018

A-544.44 lakhs. Total expenditure of the Company during 2000 = Rs. (324 + 101 + 3.84 + 41.6 + 74) lakhs = Rs. 544.44 lakhs.

• ## Question: Total expenditure on all these items in 1998 was approximately what percent of t...

Posted in: Bank PO | Date: 01/01/2018

C-69%. Required percentage = (288 + 98 + 3.00 + 23.4 + 83) x 100 % (420 + 142 + 3.96 + 49.4 + 98) = 495.4 x 100 % 713.36 69.45%.

• ## Question: The total amount of bonus paid by the company during the given period is approxi...

Posted in: Bank PO | Date: 01/01/2018

C-1%. Required percentage = (3.00 + 2.52 + 3.84 + 3.68 + 3.96) x 100 % (288 + 342 + 324 + 336 + 420) = 17 x 100 % 1710 1%.

• ## Question: What is the average amount of interest per year which the company had to pay dur...

Posted in: Bank PO | Date: 01/01/2018

D-36.66 lakhs.. Average amount of interest paid by the Company during the given period = Rs. 23.4 + 32.5 + 41.6 + 36.4 + 49.4 lakhs 5 = Rs. 183.3 lakhs 5 = Rs. 36.66 lakhs.

• ## Question: A man can row upstream at 7 kmph and downstream at 10 kmph. Find man’s rat...

Posted in: Bank Clerical | Date: 01/01/2018

C-1.5, 1.6 km/hr. Rate in still water = 1 / 2 (10 + 7) km/hr = 8.5 km/hr. Rate of current = 1 / 2(10 - 7) km/hr = 1.5 km/hr.

• ## Question: If 10, 12 and ‘x’ are sides of an acute angled triangle, how many integer va...

Posted in: Bank PO | Date: 01/01/2018

C-9. Any side of triangle is less than the sum of other two sides so in this case x < 22. Also any side of triangle is larger than positive difference of other two sides so x > 2. 2 < x < 22 Total of 19 possible values. As this is acute angled triangle x must be largest hence x > 12 and x < 22 so total of 9 possible values

• ## Question: If the circumradius of an isoceless triangle ABC is equal to AB (= AC), then ang...

Posted in: Bank PO | Date: 01/01/2018

D--2π/3. sin B = b / 2R = AC / 2 = R / 2R [Given AB = AC = R] = 1/2 B = p / 6 or 5p / 6 When B = 5p / 6, C = 5p / 6 [AB = AC ? B = C] ?B + C > p So, B = 5p / 6 not possible Hence, B should bep / 6,C = p / 6 A = p - (p / 6 + p / 6) A = 2p / 3

• ## Question: High quality music only needs frequencies up to

Posted in: Physics | Date: 01/01/2018

E-- 15kHz.

• ## Question: In frequency modulation, amplitude of modulated wave is

Posted in: NEET | Date: 01/01/2018

C- constant... AM frequency of the carrier wave remains unchanged

• ## Question: Variation in amplitude or frequency of carrier wave is called

Posted in: Physics | Date: 01/01/2018

C--+Variation in amplitude or frequency of carrier wave is called modulation...

• ## Question: Amplitude of modulated wave is in phase with

Posted in: Physics | Date: 01/01/2018

D- signal.

• ## Question: With a 30 m long coaxial cable, bandwidth can exceed

Posted in: Physics | Date: 01/01/2018

A--With a 30 m long coaxial cable, bandwidth can exceed 100MHz

• ## Question: Data in compact disc is stored in form of

Posted in: NEET | Date: 01/01/2018

B-CD data are stored as a series of tiny indentations known as “pits”, means digital signal...

• ## Question: Value of sampled signal is used to produce a

Posted in: AIPMT | Date: 01/01/2018

D-all of above. express the samples of the analog signal , we use the notation (with square brackets), where integer values of index the samples. .... Attempting to recover by ideal low pass filtering instead produces since the latter has a lower frequency.

• ## Question: Each digit in a binary number is known as a

Posted in: Physics | Date: 01/01/2018

A--- Each digit in a binary number is known as a bit...

• ## Question: Frequency of sky waves is

Posted in: Physics | Date: 01/01/2018

B- more than 3 MHz. The sky waves are the radiowaves of frequency between 2 MHz to 30 MHz.

• ## Question: A digital quantity has

Posted in: Physics | Date: 01/01/2018

A-A digital quantity has only 2 values...

• ## Question: Bit on left hand side has

Posted in: Physics | Date: 01/01/2018

C-Bit on left hand side has highest value...

• ## Question: Geostationary satellite has period

Posted in: Physics | Date: 01/01/2018

B- same as Earth....A geosynchronous satellite is a satellite in geosynchronous orbit, with an orbital period the same as the Earth's rotation period.

• ## Question: First communication satellites used frequencies of

Posted in: Physics | Date: 01/01/2018

A-First communication satellites used frequencies of 6 GHz for uplink..

• ## Question: Unwanted signal that distorts a transmitted signal is called

Posted in: Physics | Date: 01/01/2018

B--Unwanted signal that distorts a transmitted signal is called noise...

• ## Question: In FM, frequency of modulated wave varies with

Posted in: Physics | Date: 01/01/2018

A- amplitude...the alteration of the amplitude of the carrier wave, whereas FM involves changes in the frequency of the carrier wave.

• ## Question: Binary system has base

Posted in: Physics | Date: 01/01/2018

D-2. In mathematics and digital electronics, a binary number is a number expressed in the base-2 numeral system or binary numeral system, which uses only two symbols: typically 0 (zero) and 1 (one). The base-2 numeral system is a positional notation with a radix of 2.

• ## Question: Phenomena in which signal transmitted in one circuit creates undesired effect in...

Posted in: Physics | Date: 01/01/2018

D--Phenomena in which signal transmitted in one circuit creates undesired effect in other circuit is known as crosslinking..

• ## Question: Voltage signal generated by a microphone is

Posted in: Physics | Date: 01/01/2018

B-- Voltage signal generated by a microphone is analogue in nature...

• ## Question: At end of communication system, signal is converted from radio to

Posted in: Physics | Date: 01/01/2018

A--At end of communication system, signal is converted from radio to sound..

• ## Question: If frequency of modulated wave is less than frequency of carrier wave, then inpu...

Posted in: Physics | Date: 01/01/2018

A---If frequency of modulated wave is less than frequency of carrier wave, then input signal is negative...

• ## Question: Decrease in strength of signal is known as

Posted in: Physics | Date: 01/01/2018

C--Decrease in strength of signal is known as attenuation...

• ## Question: As compared to sound waves frequency of radio waves is

Posted in: Physics | Date: 01/01/2018

B- As compared to sound waves frequency of radio waves is  higher...

• ## Question: In CCIR-B system, the time between start of one H syn. pulse and next is

Posted in: Physics | Date: 01/01/2018

A-64 μs...The frequency of H pulses is 15625 Hz. Hence . T = 1/f = 1/15625 = 64 μs.

• ## Question: When the channel is noisy, producing a conditional probability of error p&n...

Posted in: Physics | Date: 01/01/2018

D--When the channel is noisy, producing a conditional probability of error p = 0.5; the channel capacity and entropy function would be, respectively,0&1...

• ## Question: Push pull amplifier is

Posted in: Physics | Date: 01/01/2018

B--- push pull amplifier is current amplifier...A push–pull amplifier is a type of electronic circuit that uses a pair of active devices that alternately supply current..

• ## Question: Which of the following is taken as reference antenna for directive gain?

Posted in: Physics | Date: 01/01/2018

C-Isotropic antenna is one which radiates equally in all directions. It is a standard reference antenna.

• ## Question: If the frequency of a wave 20 Hz, the time period is

Posted in: Physics | Date: 01/01/2018

D-0.05... T=1/f = 1/20 = 0.05..

Posted in: Physics | Date: 01/01/2018

B- Frequency modulation gives noise free reception and is used for radio broadcasts.

• ## Question: A generator is feeding power to a transmission line of characteristic impedance ...

Posted in: Physics | Date: 01/01/2018

D- both (b) and (c). Both the case, i.e., ZL > Z0 and ZL < Z0 give rise to standing waves.

• ## Question: Signal to noise ratio of microphone is defined as the ratio of output when the s...

Posted in: Physics | Date: 01/01/2018

C-- 0.1 Pa (= 0.5 x 10-4 W/m2) is taken as standard sound pressure for defining S/N ratio of microphones.

• ## Question: Consider the following statements  1. The amplitude of an FM wave is con...

Posted in: Physics | Date: 01/01/2018

B- 1,2,3. FM equipments are complex as compared to AM equipments.

• ## 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

A- 1.92 ms. (2 ms) (1 - 0.04) = 1.92 ms.

• ## Question: Which of the following has the highest input impedance?

Posted in: Physics | Date: 01/01/2018

C---CC connection has very high input impedance and low output impedance.

• ## Question: It is desired that transmission line and load should match for a range of freque...

Posted in: Physics | Date: 01/01/2018

C--When matching over a range of frequencies is desired, double stub is necessary.

• ## Question: Frequency shift keying is used mostly in

Posted in: Physics | Date: 01/01/2018

A-Frequency shift keying (FSK) is a system of frequency modulation used in telegraphy.

• ## Question: If the bandwidth is increased by 2, the γFM γAM (where &ga...

Posted in: Physics | Date: 01/01/2018

C--4. Doubling of frequency increase SNR in frequency modulation by 4. It has no effect in AM.

• ## Question: A 1000 kHz carrier is simultaneously modulated with 300 Hz, 800 Hz and 2 kHz aud...

Posted in: Physics | Date: 01/01/2018

B--1000 kHz. Frequency present in the sidebands is equal to = fc ± fm, fc ± 2fm , fc ± 3fm .

• ## Question: A carrier is simultaneously modulated by two sine waves having modulation indice...

Posted in: Physics | Date: 01/01/2018

D--0.5. m1 = 0.4, m2 = 0.3.

• ## Question: Some types of traps used in video IF amplifier of colour TV are

Posted in: Physics | Date: 01/01/2018

D-- Some types of traps used in video IF amplifier of colour TV are shunt traps, series traps, absorption traps...

• ## Question: The rate at which information can be carried through a communication channel dep...

Posted in: Physics | Date: 01/01/2018

B--Rate of information depends on bandwidth.

• ## Question: What are main topics in chemical equilibrium

Posted in: Chemistry | Date: 02/01/2018

1. Equilibrium can be attained from either side. 2. Equilibrium is dynamic in nature, i.e., at equilibrium reaction does not stop. 3. At equilibrium, there is no change in the concentration of various species. 4. The equilibrium state remains unaffected by the presence of catalyst. Catalyst helps to attain the equilibrium state rapidly. 6. The observable physical properties of the process become constant.

Posted in: Bank PO | Date: 02/01/2018

A--Photography is no longer an art form. Nowadays everyone has access to digital cameras that only need to be pointed at the subject in order to generate a perfect image. The writer of the argument apparently assumes that the selection of the subject is not an important artistic factor in photography...

• ## Question: In a single throw with 2 dices, what is probability of neither getting an e...

Posted in: Bank PO | Date: 02/01/2018

D---1/6...Probability of getting an even number in one on the first dice is (when you get (2,4 or 6) that is 3 outcomes out of 6 possible outcomes That is 3/6. Probability of NOT getting an even number id 1-3/6 = 3/6 or 1/2.........................(1) The pribability of getting a multiple of 3 is when you get 1 or 2 or 4 or 5 on the second dice Or 4/6 = 2/3 So probability of NOT getting the above is 1-2/3 = 1/3.........................................................(2) Hence the required probability is 1/2 x 1/3 or 1/6..

• ## Question: The perimeter of a rectangle whose length is 6 metre more than its bre...

Posted in: Mathematics | Date: 02/01/2018

A--360 sq. metre....l+b =42 and l = b+6 Solving b =18 and l = 24 diagonal of the rectangle = sq root of 18^2+24^2 = 30 m. Area of triangle = 1/2 (24)(30) = 360 sq m.

• ## Question: A uniformly moving train of length 480 m takes 3 minutes to completely cros...

Posted in: Mathematics | Date: 02/01/2018

E--2.4 km. speed of train = length of train / time taken to cross pole = 480/30 = 16m/s In three minute it will cover = 16 * 3 * 60 = 2880 m Of this, train length = 480 m Therefore platform = 2880 - 480 = 2400m = 2.4km

• ## 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

C---2.1 years...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

• ## 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

E--823.08 ltr...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.

• ## Question: The average marks in science subject of a class of 20 students is 68. If th...

Posted in: Bank PO | Date: 02/01/2018

D-69. The total number of marks = 20 × 68 = 1360 Add difference of marks misread against the actual marks i.e. 20 = 1360 + 20 = 1380 Now the correct average = 1380/20 = 69

• ## Question: Briefly mention the measures you would suggest to control population e...

Posted in: Bio-medical | Date: 02/01/2018

Delayed Marriages. ... Medical Facilities. ... Legislative Actions. ... Providing Incentives. ... Spread Awareness. ... Women Empowerment. ... Eradicate Poverty. ... Education.

• ## Question: What are the modifications that are observed in birds that help them fly?

Posted in: Biology | Date: 03/01/2018

(a) Birds have feathers which help them to fly. (b)Forelimbs are modified into wings for flight. (c)The avian flight muscles are used for flying. (d)The long bones are hollow and connected to air cavities to reduce weight. (e)The bones are light. (f)Feathers decrease water loss from body. (g)High metabolic rate to lift body from ground.

• ## Question: How important is the presence of air bladder in Pisces?

Posted in: Biology | Date: 03/01/2018

Gas bladder or air bladder is a gas filled sac present in fishes. It helps in maintaining buoyancy. Thus, it helps fishes to ascend or descend and stay in the water current.

• ## Question: What are the difficulties that you would face in classification of animals, if c...

Posted in: Biology | Date: 03/01/2018

If we consider specific characteristics instead of fundamental features then each organism will be placed in a separate group and the entire objective of classification would not be achieved. Classification of animals is also important in comparing different organisms and judging their individual evolutionary significance. If only a single characteristic is considered, then this objective would not be achieved.

• ## Question: What are the functions of liver?

Posted in: Biology | Date: 03/01/2018

The liver has two large sections, called the right and the left lobes. ... The liver also detoxifies chemicals and metabolizes drugs. As it does so, the liver secretes bile that ends up back in the intestines. The liver also makes proteins important for blood clotting and other functions.

• ## Question: The profit earned after selling an article for Rs. 524 is the same as the l...

Posted in: Bank PO | Date: 03/01/2018

A--Rs. 480. SP = CP + Profit and CP = SP + loss If the profit and loss is same with two different SP, then CP = (SP1 + SP2) / 2 = (524+436)/2 = 960/2 = 480

• ## Question: A large tanker can be filled by two pipes A and B in 60 minutes and 40 minu...

Posted in: Bank PO | Date: 03/01/2018

B-30 min... Part filled by (A + B) in 1 minute = 1 + 1 = 1 . 60 40 24 Suppose the tank is filled in x minutes. Then, x 1 + 1 = 1 2 24 40 x x 1 = 1 2 15 x = 30 min.

• ## Question: A bank offers 10% interest rate compounded annually. A person deposits Rs. ...

Posted in: Mathematics | Date: 03/01/2018

A-102102...Total amount after 4 years = 29282 + 26620 + 24200 + 22000 = Rs. 102102

• ## Question: My brother is 3 years elder to me. My father was 28 years of age when my si...

Posted in: Mathematics | Date: 03/01/2018

D-32 years...Father's age was 28 28 years when my sister was born. My sister's age was 4 4 years when my brother was born. Therefore, father's age was 28 + 4 = 32 28432 years when my brother was born.

• ## Question: which part of flower form it's fruit

Posted in: Biology | Date: 07/01/2018

Before a fruit can be formed, the flowers must bloom so the male and female parts can develop and produce pollen and receptive ovules. Within the flower, pollen is produced in the stamens, while the female ovules form inside a pistil.

• ## Question: Help me to calculate the value of the integral: \(\int \limits _0^1{e^{x^2}...

Posted in: WBJEE | Date: 07/01/2018

Let u=x2ux2. Then du=(x2)′dx=2xdxdux2′dx2xdx (steps can be seen here) and we have that xdx=du2xdxdu2. The integral can be rewritten as ∫xcos(x2)dx=∫12cos(u)du xcosx2dx12cosudu Apply constant multiple rule ∫cf(u)du=c∫f(u)ducfuducfudu with c=12c12 and f(u)=cos(u)fucosu: ∫12cos(u)du=(12∫cos(u)du) 12cosudu12cosudu The integral of the cosine is ∫cos(u)du=sin(u)cosudusinu: 12∫cos(u)du=12sin(u) 12cosudu12sinu Recall, that u=x2ux2: 12sin(u)=12sin(x2) 12sinu12sinx2 Therefore, ∫xcos(x2)dx=12sin(x2) xcosx2dx12sinx2 Add the constant of integration: ∫xcos(x2)dx=12sin(x2)+C xcosx2dx12sinx2C Answer: ∫xcos(x2)dx=12sin(x2)+Cxcosx2dx12sinx2C.

• ## Question: A ball is dropped from a building of height 45 m. Simultaneously another ball is...

Posted in: Physics | Date: 07/01/2018

For a ball dropped from a building, speed in the downward direction after time t is given by υy1=0+gt=−10t For a ball thrown up with υ=40ms−1, Speed after time t is given by υy2=40−10t \ Relative speed of balls =υy2−υy1=40ms−1

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

Posted in: BITSAT | Date: 07/01/2018

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

• ## Question: A bird is tossing (flying to and fro) between two cars moving towards each other...

Posted in: AIEEE | Date: 07/01/2018

Given, Speed of first car = 18 km/h Speed of second car = 27 km/h Relative speed of each car w.r.t. each other = 18 + 27 = 45km/h

• ## Question: An object falling through a fluid is observed to have acceleration given by a = ...

Posted in: Physics | Date: 07/01/2018

If a spherical body of radius r is dropped in a viscous fluid, it is first accelerated and then its acceleration becomes zero and it attains a constant velocity called terminal velocity. According to the problem, acceleration of object is given by the relation a=g-bv When speed becomes constant acceleration a = dv/dt = 0 (uniform motion). where, g = gravitational acceleration Clearly, from above equation as speed increases acceleration will decrease. At a certain speed say v0, acceleration will be zero and speed will remain constant. Hence, a = g- bv0 = 0 => v0 = g/b

• ## Question: A ball is bouncing elastically with a speed 1 m/s between walls of a railway com...

Posted in: Physics | Date: 07/01/2018

A--- The direction of ball would change after 10 secs. Then ball and the train are in relative motion and their relative velocity is zero.

• ## Question: Kunal throws his bat vertically upwards with an initial velocity of 28.2 m/...

Posted in: AMIE | Date: 07/01/2018

Ans. The height = u^2/2g = 28.2*28.2/(2*9.8) m = 40.57 m = 40.6 m (approx)

• ## Question: A 150 m long train is moving with uniform velocity of 45 km/h. The time taken by...

Posted in: Physics | Date: 07/01/2018

45kmph=12.5m/s total length discovered by train=850m+150m=1000m velocity=Dispacement/time t=s/v t=1000m / (12.5m/s) t=80s time taken to cross the bridge is 80s..

• ## Question: From the top of a building 40 m tall, a ball a thrown vertically upwards with a ...

Posted in: Physics | Date: 07/01/2018

S=-40m, u=10m/s, a=-10m/s2 By formulae s=ut+1/2 at2 -40=10×t +1/2 ×-10 ×t2 -40=10t-5t2 5t2-10t+40 On simplifying We get t2-2t+8 On simplifying We get Time t=4s

• ## Question: What do you understand by scientific attitude?

Posted in: Physics | Date: 07/01/2018

A scientific attitude is a disposition to act in a certain way or a demonstration of feelings and/or thoughts. Studies of the actions of scientists have led to lists of scientific attitudes such as displayed below.

• ## Question: Why was science called natural philosophy in earlier days?

Posted in: Physics | Date: 07/01/2018

The scientific method has ancient precedents and Galileo exemplifies a mathematical understanding of nature which is the hallmark of modern natural scientists. Galileo proposed that objects falling regardless of their mass would fall at the same rate, as long as the medium they fall in is identical.

• ## Question: What is the basic aim of science?

Posted in: Physics | Date: 07/01/2018

Either way (so-called "pure" or "applied" research), science aims to increase our understanding of how the natural world works. The knowledge that is built by science is always open to question and revision.

• ## Question: Why do we call Physics an exact Science?

Posted in: Physics | Date: 07/01/2018

Physics is called exact science because it is based on measurement of fundamental quantities. The main aim of science is to find the truth behind the various processes taking place in the universe..

• ## Question: Help me to state the law of conservation of angular momentum.

Posted in: Physics | Date: 07/01/2018

Any object that rotates has angular momentum while it's spinning. This can be anything from obvious things like a top spinning on a table to things we might not think about like a doorknob turning. Angular momentum gives us a measurement of an object's ability to keep spinning. The more angular momentum something has, the more it will want to keep rotating.

• ## Question: As a ball rises the vertical component of its velocity

Posted in: Physics | Date: 08/01/2018

B- decreases....As a ball rises the vertical component of its velocity decreases...

• ## Question: In which hills does the tapi river rise?

Posted in: Social Studies | Date: 27/02/2018

Tapi river rises near Multai in the Betul district of Madhya Pradesh at an elevation of about 752 m and flows for about 724 km before outfalling into the Arabian Sea through the Gulf of Cambay.

• ## Question: What is bond dissociation energy

Posted in: Chemistry | Date: 27/02/2018

Bond-dissociation energy (BDE or D0) is one measure of the strength of a chemical bond. It can be defined as the standard enthalpy change when a bond is cleaved by homolysis, with reactants and products of the homolysis reaction at 0 K (absolute zero).

• ## Question: What are hormones? Write any three function of hormones.

Posted in: Biology | Date: 27/02/2018

• ## Question: what is significance of lok adalats

Posted in: Social Studies | Date: 27/02/2018

Legal services at Judiciary. Lok Adalat got initiated with a strong objective to take the justice system much closer to the people. It also aim at lessening the pending litigation . Its significance lies in actual justice delivery at door step of people and actual reduction in the numbers of real litigation.

• ## Question: Please mention some good novels written by Munshi Premchand.

Posted in: Hindi | Date: 27/02/2018

Devasthan Rahasya Prema Roothi Rani Vardaan Seva Sadan Premashram Nirmala (novel) Kaayakalp Gaban Karmabhoomi Godaan

• ## Question: What is dry ice? Why is it called as dry ice?

Posted in: Physics | Date: 27/02/2018

Dry Ice is the common name for solid carbon dioxide (CO2). It gets this name because it does not melt into a liquid when heated; instead, it changes directly into a gas (This process is known as sublimation).

• ## Question: Can it be possible to clear the CLAT exam?

Posted in: CLAT | Date: 27/02/2018

Yes,,With the right information, and preparation, you can certainly clear the CLAT.

• ## Question: Which poem would you call ‘the best’?

Posted in: Creative Writing Classes | Date: 27/02/2018

Robert Browning's “My Last Duchess”...

• ## Question: what-happens-when-a-borax-solution-is-acidified

Posted in: Chemistry | Date: 27/02/2018

Boric acid is formed when brax is acidified. Na2B4O7 +2HCl +5H2O ---->2NaCl +4H3BO3