Question

Prove that gravitational force is conservativeand frictoin

Answer 1

We know that a conservative force is that force in which the path taken by the body doesn't matter in the calculation of work done.

In case of gravity, the force acts between the center of mass of the object and the C.O.M. of Earth. Hence any horizontal work done on the object would not account to the gravitational work done. Hence the gravitational work is conservative.

On the other hand frictional work done increases with the path covered by the object, even if the frictional force remains constant.