Potential Energy

The energy possessed by a virtue of its position or molecular arrangement(configuration) is called potential energy.

The potential energy is of the following three types:

• Gravitational potential energy


• 
   Elastic potential energy, and
  


• 
   Electrostatic potential energy
  

Gravitational Potential Energy

Consider a body having mass ‘m’ is lying on the surface of the earth and ‘g’ be the value of acceleration due to gravity at that place. A force ‘mg’ is required to lift the body in upward direction. Let the body is lifted to a height ‘h’. Then work done (W) is,

            W = Force x displacement

Or,      W = F x h = mg x h

Or,      W = mgh

 This work done is stored in the body in the form of gravitational potential energy. Therefore , Gravitational potential energy = mgh .