Potential Energy:

Energy is defined as capacity to do work. It may exist in many forms, that means mechanical (potential or kinetic) chemical, nuclear, thermal etc. It is also well known that energy is conserved through transformation from one form to another. The potential energy of a body is the form of energy which is stored by virtue of the work which was previously been done on that body, that means. In lifting this to some height above a datum. In this case, work is done on the body by displacing it against the force of gravity. This potential energy is converted to an equivalent kinetic energy if the body is allowed to fall from the height by developing velocity of fall. Now, let us assume the case of a deformable body subjected to certain external forces or what we call as loads. Because of the property of deformability of the body, each points of application of these forces might undergo certain displacement. Thus, the force moves through a certain distance, which is equivalent to doing work on the body, that means. a certain energy imparted to the body. One may now ask a question, 'where did all this energy go'? Because it had to be conserved.