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  1. LOGO www.themegallery.com Magnetism
  2. LOGO Magnet The first magnets were known as magnetite or loadstone.
  3. LOGO Magnetic field lines of a bar magnet
  4. LOGO Magnet Iron filings "map" of the field of a bar magnet
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  7. LOGO Cutting a magnet  An interesting characteristic of magnets is that when you cut a magnet into parts, each part will have both N and S poles. June 6, 2011
  8. LOGO Making Magnets Stroking a piece of unmagnetised iron or steel with a known magnet can make it into a magnet.
  9. LOGO Making Magnets Placing a magnet alongside a non- magnetised steel knitting needle for some time will magnetise it.
  10. LOGO The Earth – A huge magnet
  11. LOGO Electric current and magnetism
  12. LOGO Classification of materials  Ferromagnetic materials  strongly attracted by a magnetic force: iron (Fe), nickel (Ni), cobalt (Co) and gadolinium (Gd)  Paramagnetic materials  weakly attracted to magnets: Aluminum  Diamagnetic materials  when they are exposed to a strong magnetic field, they induce a weak magnetic field in the opposite direction.
  13. LOGO Ferromagnetic material
  14. LOGO Spinning electrons
  15. LOGO Domains Magnetic material with domains misaligned Aligned domains makes material highly magnetic
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  17. LOGO Non magnetic material
  18. LOGO Permanent magnet
  19. LOGO Demagnetize Heating a piece of magnetized iron or steel strongly in a flame will demagnetize it.
  20. LOGO Solenoid H = NI/ L