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How does an eraser work?

  1. Sep 23, 2008 #1
    How does an eraser (rubber, for non-US) work? Any why it works only for pencil(or graphite) , not for pen?
  2. jcsd
  3. Sep 24, 2008 #2


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    Homework Helper

    the eraser rubs the graphite off the paper. graphite is a solid and sits on top of the paper (in a thin layer). that's why you can rub it off without destroying the paper underneath.

    You can't rub off ink, because it dyes the paper--i.e., gets below the surface of the paper.
  4. Sep 24, 2008 #3


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    Science Advisor

    And rubber is used for the same reason it is used in bicycle and automobile tires; because it has good traction. It "grips" the graphite just like tires grip the road.
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