Physical Prosesses - Changing Circuit

1. Circuits
A circuit always needs a power source, such as a battery, with wires connected to both the positive (+) and negative (-) ends.
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, i.e. has no gaps.























2. Symbols
Circuits are often drawn as diagrams with these symbols:











3. Switches
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.















4. Changing circuits
Adding more batteries to a simple circuit will make a bulb brighter.















Adding more bulbs to a simple circuit will make the bulbs dimmer


















Lengthening the wires in a simple circuit will make the bulb dimmer.