MAGNETISM

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MAGNETISM

• Chapter 14..
• and you thought we were finished?

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Magnetism

• The force that acts at a distance
• Caused by magnetic field
• Strongly attracts metals like iron, nickel and
  cobalt
• Stronger for opposite poles
• Similar to electric field
• Different from electric field

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What is a magnetic field?

• Consists of imaginary direction lines coming from
  moving or spinning electrically charged
  particles a proton spinning or electrons moving
  through a wire in an electric current

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Magnetic Field

• Must have poles North or North seeking and
  South or South seeking
• The same direction as the earths
• Direction of field goes from north to south
• Opposite poles attract like poles repel (push
  away)

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Magnetic Field

• Opposites attract

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Magnetic Field

• Likes repel

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Magnets

• Object or material that attracts certain metals
  (iron, nickel, cobalt)
• Have north south poles
• 3 types permanent, temporary and electromagnet

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The Earths Magnetic Field
N S
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Magnets

• Permanent holds magnetic properties over a long
  period of time
• Temporary eventually loses magnetism (soft
  iron)
• Electromagnet electrical wire wrapped around an
  iron or steel core (used with DC electricity)

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Magnets

• Can be 2 shapes
• Bar Horseshoe

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What happens when you cut a magnet?

• You still have 2 poles for each piece of the
  magnet

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Uses for Magnets

• Compass the needle always points northward
• Electrical devices
• To put things on the refrigerator

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Similar to electric fields?

• The poles (north south) are very similar to the
  positive and negative charges
• In electricity the charges repel.in magnetism,
  the poles repel

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Different from electric fields?

• Magnetic field is a dipole field every magnet
  must have 2 poles
• Electric fields are monopoles the positive and
  negative charges can stand alone

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Magnetism

• A force that acts at a distance
• Is caused by a magnetic field
• The magnetic force strongly attracts an opposite
  pole of another magnet and repels a like pole.
• The magnetic field is both similar and different
  than an electric field.