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How do you put a uniform charge on an insulator?

  1. Sep 28, 2010 #1
    To put a uniform charge on the surface of a conducting hollow sphere one just needs to touch it at one point with an electrode.

    To put a uniform charge on the surface of an insulating hollow sphere, do you have to somehow physically spray charge all over it?
  2. jcsd
  3. Sep 30, 2010 #2
    Yes. You might also try to ionize surface atoms.
    What for?
  4. Sep 30, 2010 #3
    I would like to do some of experiment to measure the mass of an electron inside a charged spherical insulator. I think 1/2 the electrostatic energy between the electron and the charged shell would reside in the field around the electron and would therefore make it heavier.

    If we could make the electron heavy then we could make small atoms with these heavy electrons. Small atoms might fuse much more easily than normal size ones.

    That's it - I want to solve the world's energy problems and climate change problems. ;)
  5. Oct 2, 2010 #4
    There is no such thing as a perfect insulator, some materials just have extremely high resistance. Since the total charge on the sphere would be relatively small very little current would need to flow on the sphere in order for the charge to equalize. While the time for a small charge to flow through high resistance would be greater then low resistance I believe the time frame would be a few minutes at the most.
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