Ammeter

Key Stage 3

A picture showing an analogue ammeter.

An ammeter is a measuring device used to measure electrical current.

Ammeters are added in series to a circuit to find the current flowing through the circuit.

An ideal ammeter has zero resistance because otherwise adding an ammeter to a circuit would change the current.

Ammeters can be analogue with a needle pointing to numbers on a dial or it can be digital with a number display.


An ammeter placed in series with a bulb.

An ammeter is a measuring device used to measure electrical current.

Ammeters are added in series to a circuit to find the current flowing through the circuit.

An ideal ammeter has zero resistance because otherwise adding an ammeter to a circuit would change the current.

Ammeters can be analogue with a needle pointing to numbers on a dial or it can be digital with a number display.

Measuring the Current through components in series.

To measure the current through bulb 1 the ammeter can be placed anywhere in this series circuit.	To measure the current through bulb 2 the ammeter can be placed anywhere in this series circuit.

Measuring the Current through components in parallel.

To measure the current through bulb 1 the ammeter must be placed in series with bulb 1.	To measure the current through bulb 2 the ammeter must be placed in series with bulb 2.