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The Lights Are Back On
That’s better, I’ve mended the fuse and the lights are back on. I can show you how the lights work by looking at my wand. Small batteries power the light in this wand so it is safe to use.
The battery is connected to the light and then the light is connected back to the battery. This forms a circuit, a bit like the ring main in my house. The electricity flows out from the negative pole of the battery, through a wire to the light bulb and then back to the positive pole of the battery. If the circuit is broken, the electricity will not flow round the circuit and the light won’t work.
Have a look at my book of wisdom to find out more about circuits then try playing my circuit game to see if you can make the light on my wand work.
Circuit Diagrams
People who work with electricity have a special code. They use symbols to describe the circuits they are working on. When they draw a circuit using these symbols it is called a circuit diagram. These are some of the symbols they use.
Lightbulb
Motor
Switch
Cell
(battery)
On the symbol for a cell the fat line is the negative end the long thin line is the positive end.
A circuit with a single cell (battery), a switch and a light bulb would look like this:
The Wand Game
Make my wand light up by dragging the pieces from the left onto the grid to create a circuit.
You’ll need the Flash plug-in to view the above activity. Download the Flash plug in here.
Next page: Quiz
Switch safety
We use switches in circuits to turn the flow of electricity on and off. When you turn your bedroom light on at night you use a switch. They are very important because they let you control the flow of electricity without touching it.
Never touch a switch with wet hands.
To save energy
Remember to turn the lights out when you leave a room empty.
Remember to switch TV and computers off when you have finished using them.
