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A circuit with a battery cell, bulb and switch
Image caption,
Adding more batteries to a simple circuit will increase the electrical energy, which will make a bulb brighter.

Circuits

Electricity can flow through the components in a complete electrical circuit.

A circuit always needs a power source, such as a battery, with wires connected to both the positive (+) and negative (-) ends. A battery is made from a collection of cells connected together.

A circuit can also contain other electrical components, such as bulbs, buzzers or motors, which allow electricity to pass through.

Electricity will only travel around a circuit that is complete. That means it has no gaps. You can use a switch in a circuit to create a gap in a circuit. This can be used to switch it on and off.

When a switch is open (off), there is a gap in the circuit. Electricity cannot travel around the circuit. When a switch is closed (on), it makes the circuit complete. Electricity can travel around the circuit.

A circuit with a battery cell, bulb and switch
Image caption,
Adding more batteries to a simple circuit will increase the electrical energy, which will make a bulb brighter.

More on Electricity

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