Magnets are useful things.
• Magnets can be used to hold cupboard doors shut.
• They are used in electric motors and generators.
• They are used in headphones and loudspeakers.
• They have fun uses - for example, magnetic letters.

This child is learning to spell using magnetic letters on the board

1) Think about your own home. Can you suggest some other uses for magnets?

Permanent magnets

Permanent magnets come in different shapes and sizes. They can be used to attract other objects - for example, paper clips made of steel.
A permanent magnet is an object which stays magnetised for a long time. It doesn't stop being a magnet after it has been used.

Magnetic materials

Some materials are attracted by magnets. Other materials are not.
A material which is attracted by a magnet is called a magnetic material.

Permanent magnets come in different shapes. This shape is a bar magnet

2) Paper clips are made from a magnetic material. What material is this? (You will find the answer higher up on this page.)

Some people imagine that all metals arc magnetic materials. Are they correct?
Use a permanent magnet to test a number of different materials. Which are attracted by the magnet?
Show your results in two lists: magnetic materials and nonmagnetic materials.

Iron and steel

Iron is a magnetic material. Steel is mostly made of iron, so most types of steel are also magnetic.
Nickel and cobalt are two other magnetic metals. Nowadays many small, strong magnets are made using a metal called neodymium.
Other metals such as aluminium and tin are non-magnetic. The picture shows how steel and aluminium cans can be separated using a powerful magnet.

electromagnet steel can aluminium cans and steel cans aluminium cans conveyor belt

3) a: Are steel cans magnetic or non-magnetic?
b: Are aluminium cans magnetic or non-magnetic?

$A+I$: 4) It is important to recycle cans because they are made from valuable materials. Write a paragraph to describe how steel and aluminium cans can be separated using a magnet, as shown in the diagram.

SE: Some permanent magnets are stronger than others. They attract magnetic materials with a stronger force.
Compare three permanent magnets. Devise your own method to decide which is the strongest and which is the weakest.
When you have completed your work, compare your method with the methods used by others in the class. Which do you consider the best, and why?

Summary

• A permanent magnet remains magnetic after it has been used.
• Magnetic materials are attracted by permanent magnets.