23/09/09

Electric circuits

An electric circuit is a path along which electricity can flow to make up a circuit you need a battery ,a buld and two wires .the wires are used to join the battery to the bulb .the batteries job is to pash an electric current through the wires and the bulb .the bulb the bulb light yo as the current flows through it.

Meters and switches

If you want to measure the size of the current ,you have to put a meter into the circuit .current is measured in amperes (A) or amps for short.

The meter for measuring current is called an ammeter.

If you want to turn the bulb on and off easily you shuld . a switch work by opening and closing a gap in the circuit .when the switch is turned off , a gap opens up .this stops the flow of current all round the circuit.

When the switch is turned on, the gap is closed .this maks a complete circuit and the current can flow.