Series and parallel circuits

O/L Science · G.C.E. Ordinary Level · Grades 10–11

Aim

To compare current and voltage in series and parallel circuits.

Apparatus

• A 6 V battery
• Identical bulbs (12 Ω)
• Ammeter, voltmeter, wires

Method

1. Connect bulbs in series; measure the current and the voltage across one bulb.
2. Repeat with a different number of bulbs.
3. Now connect them in parallel and measure again.
4. Observe the brightness.

Conclusion

In series the current is the same and the voltage is shared (more bulbs → dimmer). In parallel every bulb gets the full voltage and the currents add.