The universality of the law of gravitation

Newton’s law of gravitation is equally valid for anybody whether it is small or large. This law does not depend on the states of the two bodies (solid, liquid, or gas), their chemical composition, their temperature, the intermediating medium. This law is valid in case of a small distance in the earth or even in case of a large distance between stars, planets, etc in the universe. For the above causes this law is said to be universal.

But there are some limitations or invalidness of this law. According to Einstein’s theory of relativity, the mass of a body depends on its velocity. Again the distance between the two bodies is different relative to the two observers.

This is not valid in case of atomic distance (10^-7cm or less than it) and in the case of a body that is moving with a velocity equal to the velocity of light.