Introduction
Electrostatic force is a conservative force. Work done by an external force (equal and opposite to the electrostatic force) in bringing a charge q from a point R to a point P is VP – VR, which is the difference in potential energy of charge q between the final and initial points. Also Potential at a point is the work done per unit charge (by an external
agency) in bringing a charge from infinity to that point. Whereas Potential energy stored in a system of charges is the work done (by an external agency) in assembling the charges at their locations.