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• Magnetism

  • is the ability of a material to attract iron, steel and its alloys. 
• A magnet is any material that attracts iron or materials containing iron
• • When a group of atoms or molecules called magnetic DOMAINS are aligned, the material made up of these atoms have strong magnetic properties
• • All magnets have two poles. 
  • North pole 
  • South pole
• • Each end of the magnet is called a magnetic pole 
• Magnetic poles are always in pairs
• Magnetic monopoles don't exist.
• • Like poles repel. Unlike poles attract
• The force can either push the magnets apart or pull them together.
• • Magnetic field lines show both the direction and the strength of a bar’s magnetic field
• • Whether a material is magnetic depends on the material’s atoms 
• • The atoms group together in tiny areas called domains. Each domain is like a tiny magnet.
• In most materials, such as copper and aluminum, the magnetic fields cancel each other out because the domains are randomly oriented
• • In materials such as iron, nickel, and cobalt, the north and south poles of the atoms in a domain line up and make a strong magnetic field. 
• The arrangement of domains in an object determines whether the object is magnetic.
• The domains of a magnet may not always stay lined up.
• The domains of a magnet may not always stay lined up.

  • When domains move, the magnet is demagnetized, or loses its magnetic properties.
• Ways to Demagnetize (Move domains)

  • Dropping a magnet or hitting it too hard. 
  • Putting the magnet in a strong magnetic field that is opposite to its own. 

  Increasing the temperature of a magnet
• • heat can destroy magnetism
• 1. Ferromagnetic Materials - have very strong magnetic properties since they are mostly made up of iron.  
• 1. Paramagnetic Materials - materials that are slightly attracted to magnets. 
• • Diamagnetic Materials materials that are slightly repelled by magnets