• When an electric current flows in a wire it creates a?magnetic field?around the wire
• By winding the wire into a?coil?we can?strengthen?the magnetic field by concentrating the field lines
• If this wire is wound around a soft magnet, such as an iron, then an electromagnet is made
  • The electromagnet is magnetic?only?when current flows through the wire

   

Electromagnets are made up of a coil of wire wrapped around an iron core

• The strength of an electromagnet’s magnetic field may be increased by:
  • Increasing the?current?in the coil
  • Adding more?turns?to the coil

   

• The magnetic field around an electromagnet has the same shape as the one around a bar magnet
• The field can be?reversed?by reversing the direction of the?current
  • However, bar magnets are always magnetic, unlike electromagnets

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