KEY IDEAS

• Magnetism is a force
• Magnets can produce both ‘pushes’ and ‘pulls’
• Some materials are magnetic and others are not
• Static electricity, which is different from magnetism, exerts a force which behaves like magnetism

EXAMPLE QUESTIONS

• What do magnets do?
• Can magnets ‘push’ as well as ‘pull’
• Which materials can be magnets?
• When have you experienced static electricity?
• How can you create static electricity?

MAGNETISM EXERTS A FORCE

• Certain metals, such as iron, steel, cobalt and nickel, attract each other when the atoms in the metals are aligned in a particular way.
• This effect creates a force called magnetism. Magnetic substances can be made into magnets.
• Only iron, nickel, and cobalt are natural magnets.
• Alloys of these metals can also be magnetic.
• Magnets both attract and repel each other, depending on how they are placed relative to each other.
• Magnets have two distinct ends called north and south poles.
• These ends are attracted either to magnetic north or magnetic south poles on earth.
• Non-magnetic substances are neither attracted nor repelled by magnets.

STATIC ELECTRICITY

• Static electricity behaves like magnetism but is different.
• All things are made up of positive and negative charges.
• Most objects are neutral because the positive and negative charges balance.
• Static electricity is caused by an imbalance of these charges.
• Charges can build up on the surface of an object.
• If you rub a balloon on your jumper it will ‘stick’ to the wall as a result of the opposite charges on the two surfaces attracting each other.
• When your hair sticks up after brushing it, this happens because the like charges on the surface of your hair repel each other.