Magnets
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What are the only four magnetic materials?
Iron, steel, nickel and cobalt are the only magnetic materials
What direction do magnetic field lines travel?
Magnetic field lines travel North to South
What do magnetics attract?
Magnets attract ferromagnetic metals
What is a permanent magnet?
A permanent magnet is an object made from a material that is magnetised and creates its own persistent magnetic field
What is an electromagnet?
Electromagnets are a soft metal made into a magnet by the passage of an electrical current through a coil surrounding it
How do you make a temporary magnet?
Stroke a piece of iron or steel such as a needle along a permanent magnet
Name three things that effect the strength of an electromagnet
• Number of coils • Size of current • Material of core