Poles of a Magnet

• The ends of a magnet are called?poles
• Magnets have two poles: a?north?and a?south

Poles of a Magnet

The Law of Magnetism

• When two magnets are held close together, there will be an attractive or repulsive force between the magnets depending on how they are arranged:

Opposite poles attract; like poles repel

• The Law of Magnetism states that:
  • Two?like?poles (S and S or N and N)?repel?each other
  • Two?unlike?poles (S and N)?attract?each other

   

• The attraction or repulsion between two magnetic poles is an example of a?non-contact force

• Magnetic materials can be?soft?or?hard
• Magnetically soft materials (e.g. iron):
  • Are?easy?to magnetise
  • Easily lose their magnetism (temporarily magnetised)

   

• Magnetically hard materials (e.g. steel):
  • Are?difficult?to magnetise
  • Do not easily lose their magnetism (permanently magnetised)

   

• Permanent magnets are made out of magnetically?hard?materials
• Electromagnets are made out of magnetically?soft?materials
  • This means that electromagnets can be made magnetic or non-magnetic as an when required

   

A steel pin will be attracted when an electromagnet switches on but not when it switches off. It is always attracted to a permanent magnet?

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