Charge may be negative ,positive or zero but the mass is always positive.
Force between two charges can be repulsive or attractive but in the case of mass,the gravitational force between two mass is always attractive.
Corrosion is defined as the chemical or electrochemical degradation of metals due to their reaction with the environment. The corrosion of iron, better known as rusting, is an oxidation-reduction process that destroys iron objects left out in open, moist air.
diamagnetism refers to a type of magnetism which forms in opposition to an external magnetic field and disappears when the external field is removed; paramagnetism refers to a type of magnetism that forms along the direction of an external magnetic field and disappears when the external magnetic field is removed; ferromagnetism refers to a type of magnetism in materials which forms along the direction of the external magnetic field and can remain when the external magnetic field is removed.
population inversion occurs while a system (such as a group of atoms or molecules) exists in a state in which more members of the system are in higher, excited states than in lower, unexcited energy states.
The atmosphere of the sun is composed of several layers, mainly the photosphere, the chromosphere and the corona. It's in these outer layers that the sun's energy, which has bubbled up from the sun's interior layers, is detected as sunlight. The lowest layer of the sun's atmosphere is the photosphere.
Earth passes through the comet's path, and tiny pieces of rocks and minerals from the tail enter Earth's upper atmosphere, burning up as "shooting stars." The streak of light in this remarkable photograph is a "shooting star," a tiny speck of space debris burning up as it enters Earth's atmosphere
The most basic cause for winds to blow is the existence of a pressure difference between two locations on the earth. A wind is nothing but movement of gases from one place to another. So when there is a low pressure area the gases from high pressure area move to occupy that area and hence the wind blows.