The Closed Circuit

• In application which needs the use of current, the components are set in the form of circuit.
• As indicated in given the fig.

• For any closed circuit, these things should always notice.

1.      There ought to be a source of voltage. Without applied voltage current may not flow.

2.      There ought to be a full path of current flow, from one of side of the applied voltage source, through the external circuit, and then returning to the other side of the voltage source.

3.      Normally the current path has resistance. The resistance in the circuit for the reason of either producing heat or restricting the amount of current.