Electric potential energy is defined as the total potential energy that a unit charge will have if it is located anywhere in space. Simply put, the electric potential energy of a charge or system of charges is the total work done by an external agent in bringing a charge or system of charges from infinity to the original setup without undergoing any acceleration. It is a scalar quantity with only magnitude and no direction. Its symbol is the letter V, and it is measured in Joules.
Electric Potential Formula:
The potential energy of a charge in an electric field is measured by the work done in moving the charge from infinity to that point against the electric field. The electric potential energy of the system is; (if two charges q1 and q2 are separated by a distance d):
U = [1/(4πεo)] × [q1q2/d]
Where
- The two charges are q1 and q2
- d is the distance between two charges
- εo is The permittivity of free space (8.85×10⁻¹²C²N⁻¹m⁻²)
When two similar charges (two protons or two electrons) are brought together, the system’s potential energy increases. When two opposite charges, such as a proton and an electron, are brought together, the system’s electric potential energy decreases.