The simplest complete circuit is a piece of wire from one end of a battery to the other. An electric current can flow in the wire from one end of the battery to the other, but nothing useful happens.

This is called electromagnetic induction close electromagnetic inductionThe production of a potential difference (voltage) when a conductor, such as a wire, is moved through a magnetic field or ...

Series and Parallel Circuit Series and parallel circuits are two fundamental configurations in electrical circuits, each with distinct characteristics that affect how electricity flows through them.