Magnetism

• Magnetic material


  Any material that is strongly attracted to a magnet
• Examples of magnetic materials

  Iron, nickel, cobalt, steel
• Magnet


  Can exert a force on another nearby magnet or magnetic material
• Examples of magnets

  Bar magnets, horseshoe magnets
• Poles of a magnet

  North pole and south pole
• Magnetic force at the poles

  The force is strongest near the magnet's poles
• Rule for like poles

  Like poles repel each other
• Rule for unlike poles


  Unlike poles attract each other
• Attraction and repulsion


  Examples of non-contact forces between two magnetic poles
• Permanent magnet


  Produces its own magnetic field
• Induced magnet


  A material that becomes a magnet when it is placed in a magnetic field
• Induced magnetism


  Always causes a force of attraction
• When an induced magnet is removed from a magnetic field

  It loses most or all of its magnetism quickly
• Test for a magnetic material

  See if it is attracted to both ends of a known magnet
• Test for a magnet

  See if it can be repelled by one end of a known magnet