Static Electricity

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Static Electricity

• Summary

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Only two types of charge!

• Positive Charge (protons therefore in nuclei of
  atoms )
• Negative Charge (electrons therefore orbiting
  atoms and can be brushed off onto other atoms
  making ions

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Only electrons move

• Positive Charged Object too few electrons
• Negative Charged Object too many electrons
• Net charge is ALWAYS due to ELECTRON transfer
  protons moving about would change the elements
  you are dealing with.

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Opposite Charges attract
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Like Charges Repel
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It all depends on gravity

• Whether you can see a charged object react to
  another one depends on weight. Two forces are in
  operation electric force and gravitational
  force.
• If the electric force is bigger the object can be
  seen defy gravity or in the case of the object
  on the left inertia and friction !

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Charging by Friction

• Some objects are more attractive to electrons
  than others. If you rub a balloon (very
  attractive to other atoms electrons) together
  with a woollen jumper. It will steal some of
  the electrons and leave the jumper postive.
• The balloon will have become negatively charged
  by friction.

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Charging by Induction

• If the balloon is brought near to a neutral
  object the charged region around it (its electric
  field) will affect the electrons in the neutral
  object. It will make them move away from it
  giving the surface of the neutral object near to
  the balloon a positive charge.
• The balloon will then be attracted to it and will
  stick to it.