GoalSay that some electrical things use mains electricity, some use cells, and some can use either.
New words
mains · the electricity that comes along wires into our homes and schoolscell · a small store of electricity that you can carry aboutsocket · the place in a wall where a plug goes in
Explanation
Electricity comes to our homes along wires from far away. We call it mains electricity. A plug fits into a socket in the wall, and the mains electricity flows to the machine. Big machines, such as a television or a printer, use the mains. A cell is a small store of electricity. A cell has its own electricity, so we can carry it anywhere. A torch and a toy robot use cells. A radio can use either: cells on a trip, or the mains at home. Cells run out after a time, so they must be changed.
Worked examples
The television stays in one place. A cable joins it to a wall socket, and mains electricity flows in.
Ali goes camping. There is no socket in a tent, so he takes a torch with cells.
A small radio can play with cells in the park, and with a plug at home.
Class activity
Cells or mains? (with an adult): collect six electrical things, such as a torch, a clock, a toy and a radio. Look for a flat lid where cells go, or a cable that ends in a plug. Draw two columns and write each name in the right one. Things that have both go in the middle. Do not plug anything in.
Practice
1
What do we call the electricity that comes out of a wall socket?
Mains electricity.
2
Which one needs a plug and a wall socket?
B, the television.
3
Why is a torch better with cells than with a long cable and a plug?
You can carry it anywhere, such as outside or into a tent, where there is no socket.
4
A clock can work with cells. It can also plug into the wall. Where does it go in the diagram?
In the middle, because it can use cells and it can use the mains.
