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Metal sphere and charges:

  1. May 8, 2008 #1
    I'm trying to get a better understanding of this sort of thing. Here is what I know...

    A postive point charge "q" is placed at the center of an uncharged metal sphere insulated from the ground. The outside of the sphere is then grounded from the outside. Then the ground wire is removed. A is the inner surface and B is the outer surface of a metal sphere.

    Thus, the charge on A is -q and there is no charge on B.

    Now my question is that, what does the grounding wire have anything to do with this? Is it the thing that allows charges to escape into the ground making it less charged?

    Also, instead of a postive point charge at the center, what if it was negative point charge at the center?, would the charge on B (Outer surface) be, -q then A (inner surface) is +q ?

    I'm just trying to think how to properly think about this sort of arrangement as a whole. Thanks for any help :+)
  2. jcsd
  3. May 9, 2008 #2


    Staff: Mentor

    After grounding there is no charge on the sphere
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