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Homework Help: Sphere's Electric Potential HELP

  1. Jan 17, 2008 #1
    Sphere's Electric Potential...HELP!!

    1. The problem statement, all variables and given/known data
    A 2.04-mm-diameter ball bearing has 8.710×10^9 excess electrons. What is the ball bearing�s potential?


    2. Relevant equations



    3. The attempt at a solution
    V = (1/4*pi*Eo) * (Q/r)
    Eo = 8.85 x 10^-12
    Q = 1.6x10^-19 * 8.71x10^9
    r = 0.00204/2
    V = 12308.78 V

    Can someone tell me what I am doing wrong???
     
  2. jcsd
  3. Jan 17, 2008 #2
    Why are you multiplying your excess charge by Epsilon-not to get Q?
     
  4. Jan 17, 2008 #3
    nevermind I just got it...thanks though!
     
  5. Jan 17, 2008 #4
    Great!
     
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