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Current in series circuits

You can investigate current flowing in a series circuit by connecting the following circuit.

Put one ammeter in position A1 and record the reading in a suitable table.

Then move the ammeter to position A2 and repeat and then to position A3.

Current in series circuit

Results

A1 = 0.8A.

A2 = 0.8A.

A3 = 0.8A.

Conclusion

The current in a series circuit is the same at all places in the circuit.

An electric current is a flow of charged particles.

The particles flow continually right round the circuit and through the cell – there is nowhere else for them to go.

So, the electric current is the same everywhere in a series circuit

Circuit with a cell, closed switch and two lamps connected in series. An ammeter between the cell and switch is labelled 'Is = 3 A'; an ammeter after the first lamp is labelled 'I1 = 3 A'; and an ammeter after the second lamp is labelled 'I2 = 3 A'.
Figure caption,
Circuit with a cell, closed switch and two lamps connected in a series

Question

Look at the series circuit below - what is the reading at?

a) Position 1.

b) Position 2.

c) Position 3.

Circuit with a cell, switch, ammeter and two lamps in series. Point 1 is between the switch and first lamp, point 2 is between the two lamps and point 3 is between the second lamp and the cell. The ammeter reads 0.1 A when the switch is closed.

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