Law of Conservation of Energy
Statement Energy can neither be created nor be destroyed, however, it can be transformed from one form to another.
According to this law energy may change its form within the system but we cannot get one form of energy without spending some other form of energy. A loss in one form of energy is accompanied by an increase in other forms of energy. The total energy remains constant. Proof For the verification of this law in case of mechanical energy (Kinetic and potential energy). Let us consider a body of mass ‘m’ placed at a point P which is at a height ‘h’ from the surface of the earth. We find total energy at point P, point O and point Q. Point Q is at a distance of (h-x) from the surface of earth.