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Homework Help: Transfer of Electrons

  1. Sep 16, 2007 #1
    A plate carries a charge or -3.0 microC) while a rod carres a charge of +2.0 microCs. How many electrons must be transferred from the plate to the rod so that both obejcts have the same charge?

    e = 1.6 X 10^-19 C. 6.25 X 10^18 e per C of negative energy..

    What I've done is -3.0 mC/6.25 X 10^18= -4.8 X 10^11. 2.0 mC/ 6.25 X 10^18= 3.2 X 10^11. Added up is 1.6 X 10^11

    The solution is 1.6 X 10^13 however I keep getting 1.6 X 10^11. Can someone help me out with this? What am I doing wrong? Thanks!
    Last edited: Sep 16, 2007
  2. jcsd
  3. Sep 16, 2007 #2


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    I get 1.6 X 10^-13 electrons. Check your units. Remember that:

    [tex]1\mu C=10^{-6}C[/tex]
  4. Sep 16, 2007 #3
    Would you be able to show me how you worked that because now I am getting -1.6 X 10^-25. I'm completely confused. Thanks.
  5. Sep 16, 2007 #4


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    Ok, well let me ask you this:

    How much charge moves from one to the other so they have equal charge?

    Once you know this, how did you convert the charge measurements to number of electrons?
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