Flow Of Current

A current is any motion of charge from one region to another. The illustration below shows two bodies at different potentials. When these are connected with a wire, free electrons flow from B to A until both bodies attain the same potential, after which the current ceases to flow. Current flows if a potential difference exists throughout a conductor. This branch of physics dealing with charges in motion is called current electricity.

The amount of charge flowing through a given cross-section of a conductor per unit time constitutes electric current.

When a battery or a cell is connected across the ends of a conductor, the direction thus set up exerts a force on the free

electron causing them to move as shown in the figure. The arrows give the direction of the conventional current.

Current is a scalar quantity. The direction of conventional current in any circuit is the direction in which the positive charges flow.

The electrons do indeed flow. When the circuit is closed, an electric field is set up in the entire wire from the generating plant to the user and back again on another wire -- a closed circuit is required! A wire is a

conductor precisely because some of the electrons are free to move when pushed by an electric field.

The closed circuit is required so the electrons can flow in a closed circuit; no electrons are lost!