An electric circuit is a path for electricity to flow. It needs a source (like a battery), wires, a bulb and often a switch. Electricity only flows when the circuit is complete (closed). A bulb lights up only when electricity can travel all the way round the circuit and back to the source. There are two main ways to connect the parts.
Series circuit
In a series circuit, the parts are joined one after another in a single path. If one bulb blows, the whole path is broken and all the bulbs go off. Adding more bulbs makes each bulb dimmer. A simple torchlight often uses a series circuit.
Parallel circuit
In a parallel circuit, there is more than one path. If one bulb blows, electricity still flows through the other paths, so the other bulbs stay lit.
Example
Homes use parallel circuits. You can switch off your bedroom light while the kitchen light stays on.
Remember
- A circuit must be closed to work.
- Series: one path — one break stops all.
- Parallel: many paths — others stay on.