Magnetism can cause forces to act without any contact. By understanding how permanent magnets and electromagnets work, we can describe and explain their uses in the world around us.
How many poles does a magnet have?
What would happen if we put a North and a North pole together?
They would attract
They would repel
How do we tell if an object is magnetised?
It picks up aluminium cans
It attracts another magnet
It repels another magnet
What kind of magnetic field does a current in a wire produce?
What is a solenoid?
A coil of wire around which a magnetic field has been produced
A manual switch
A coil of wire in which a voltage has been induced
What is an electromagnet?
A magnet made from magnetised iron
A magnet produced by a current in a conductor
A magnet made from aluminium
What can we add to an electromagnet to make it switch off rapidly?
An aluminium core
A plastic core
An iron core
What effect does increasing the number of coils have on an electromagnet?
Increases the strength of the magnetic field
Decreases the strength of the magnetic field
Which of the following is a way to induce a voltage in a wire?
Moving the wire between the poles of a magnet
Moving the wire near a battery
Moving the wire through the air at random
How do we make the induced voltage greater?
Form the wire into a coil
Wrap the wire around a plastic core
Keep the wire completely still inside the magnetic field