Key learning points

1. When there is an electric current in a wire, there is a magnetic field around the wire.
2. When there is an electric current in a coil of wire, the magnetic field around each loop adds to make a stronger field.
3. An electromagnet is made by wrapping a coil of wire around a core.
4. An electromagnet is a magnet that can be turned on with an electric current, and turned off.

Keywords

• Magnetic field - this exerts a force on magnets and magnetic materials

• Coil - a wire wound round in loops and looks like a spring

• Core - the centre of an electromagnet around which a wire is wound to make a coil

• Turn - a single loop of wire in a coil

• Electromagnet - a magnet made using a coil, a core and a power supply

Common misconception