Electrostatic Forces 2

A force is a push or pull.

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 What causes this to happen?
The piece of paper is greatly enlarged so you can see what happens.
 
  • When you rub a plastic ruler through your hair, some of the electrons are transferred from your hair to the ruler. The ruler has a net (overall) negative charge. (Sorry, the - charges are a little hard to see.)
  • When the ruler is brought near the neutral bit of paper, the electrons in it are pushed toward the bottom of the paper.(remember why?)
  • The positive charges remain, and so the top surface of the paper becomes positively charged.
  • This creates an attracting electric field between the ruler and the piece of paper. Since the paper is very light, it is attracted towards the ruler.
  • This is called charging by induction.
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