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Static electricity and method of seperating

  1. Feb 11, 2006 #1
    The figure below shows an electrostatic method of separating conducting and non-conducting spheres


    Why do the conducting spheres fall off from the roller while the non-conducting spheres have to be scrapped off?

    Thanks for the help.
  2. jcsd
  3. Feb 11, 2006 #2


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    What is the significance of conducting?
  4. Feb 11, 2006 #3
    Not too sure... Is the answer something about non-conductors holding the charge at the surface but charges in conductors flow throughout the material. But I thought that all the spheres will become negatively charged upon contact with the negatively charged roller.

  5. Feb 12, 2006 #4


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    For the non-conducting material, the mobile charges (electrons) do not move so readily, so electrons will not flow onto the positively charged non-conducting material

    In the 'conductor', the mobile charges (electrons) readily flow thus reducing the positive charge while the conducting material traverses the arc.
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