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.

Potential difference in series circuits Try the experiment online Resistors in series Test your knowledge Resistance ® close resistance (R)How difficult it is for current to flow. increases when ...

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.