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Electricity - polarization/grounding

  1. Jan 11, 2009 #1
    1. The problem statement, all variables and given/known data

    http://img99.imageshack.us/img99/2530/electronsvc5.jpg [Broken]
    http://g.imageshack.us/img99/electronsvc5.jpg/1/ [Broken]

    2. Relevant equations


    3. The attempt at a solution

    So in step 3, the positive ball Y is grounded. But protons can't move into the ground and all (most) of the electrons are in ball X. I was thinking the electrons in ball X were too heavily attracted by ball + to travel through ball Y to get to the ground.

    So the answer should be X = negative, and Y = positive, right? Because nothing really happened when it was grounded...
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Jan 11, 2009 #2
    It is possible that Y neutralized while it was grounded...electrons from the ground could come up and neutralize Y (you could expect current when there is a potential difference).
  4. Jan 11, 2009 #3
    But then after Y is neutralized, the electrons would still move over to X because of the + ball attracts them while they're still connected. So would X still be negative and Y positive?

    THEN I see in step 5 that the + ball is removed before the balls are removed from each other. Is this implying they neutralize each other after the + ball is taken away?

    EDIT: OK, the answer turned out to be negative and negative, WHICH MAKES NO SENSE. How can protons travel through the wire into the ground?!
    Last edited: Jan 11, 2009
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