Electric potential:

The electric potential difference is the difference in electric potential (V) between the final and the original location when work is done upon a charge to change the potential energy of it. In equation form, the electric potential difference is Electric potential is a location dependent quantity which expresses the amount of potential energy per unit of charge at a specified location.

When a Coulomb of charge has a relatively large quantity of potential energy at the given location, then that location is said to be a location of high electric potential. Similarly, if a Coulomb of charge possesses a relatively small quantity of potential energy at a given location, then that location is said to be a location of low electric potential. The electric potential at the point in space is the electrical potential energy divided by the charge which is associated with the static electric field. It is the scalar quantity, which is measured in volts.

Work should be done on a positive test charge to move it through the cells from the negative terminal to the positive terminal. This work would increase potential energy of charge and therefore increase its electric potential. As the positive test charge moves through the external circuit from positive terminal to the negative terminal, it decreases its electric potential energy and thus is at low potential by the time it returns to the negative terminal through the battery.

Force and potential energy are directly proportional to each other. As an object moves in direction that the force accelerates it, the potential energy of it decreases. For certain forces, it is possible to define the "potential" of a field so that the potential energy of an object because of a field is dependent only on the position of the object with respect to the field. 2 such forces are the gravitational force and the electric force in the absence of time-varying magnetic fields. The potential of the electric field is known as electric potential.