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Need help with Charged objects and Electron Force

  1. Feb 16, 2009 #1
    1. The problem statement, all variables and given/known data
    A plate carries a charge of -3microC, while a rod carries a charge of +2microC. How many electrons must be transferred from the plate to the rod, so that both objects have the same charge?


    2. Relevant equations
    N= q/e


    3. The attempt at a solution
    I tried finding the amount of electrons and I stopped there, I really don't know how to go about with this problem.
     
  2. jcsd
  3. Feb 16, 2009 #2

    Redbelly98

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    Before worrying about electrons, how much charge (in microC) must be transferred from the plate?
     
  4. Feb 16, 2009 #3
    1/2 microC's?
     
  5. Feb 16, 2009 #4

    Redbelly98

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    Let's see what happens in that case.

    The -3 μC plate loses 0.5 μC, and so ends up with a charge of -3.5 μC.

    The +2 μC rod gains +0.5 μC charge, ending up with 2.5 μC.

    The final charges, -3.5 and +2.5 μC, are not equal. So no, it would not be 0.5 μC transferred.

    The charges should be equal in magnitude and sign, (either both +, or both -) after the charge transfer.
     
  6. Feb 16, 2009 #5
    wow thx
     
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