How the current flows in a wire.
We know that electric current is a flow of electrons in a metal wire (or conductor) when a cell or battery is applied across its ends. A metal wire has plenty of electrons in it.
- When a metal wire has not been connected to a source of electricity like a cell or a battery, then the electrons present in it move at random in all the directions between the atoms of the metal wire.
- When a source of electricity like a cell or a battery is connected to the ends of the metal wire, then an electric force acts on the electrons present in the wire. Since the electrons are negatively charged, they start moving from negative end to the positive end of the wire. This flow of electrons constitutes the electric current in the wire.