We have seen that when a force does work on a system the system acquires motion energy, i.e. kinetic energy . However, another possibility is the work simply stores the energy in the system without any change in kinetic energy. This stored energy is called potential energy .
Potential energy is the energy stored in a system due to the position of the parts of the system.
In short, potential energy is position energy . The reason for the minus sign will become evident later. This location is called the datum or reference location for gravitational potential energy. This location is called the datum or reference location for elastic potential energy. A force is said to be conservative if the work it does depends on only the starting and ending points of the displacement and not on the path connecting the starting and ending points.