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Potential energy of 3 charges

  1. Sep 6, 2009 #1
    1. The problem statement, all variables and given/known data

    Three point charges Q1 = 2.9 mu or micro C, Q2 = 4.9 mu or micro C and Q3 = 3.9 mu or micro C, are arranged as shown.

    2. Relevant equations

    PE=k(q1q2/r+q1q3/r+q2q3/r)
    k=8.99e9

    3. The attempt at a solution

    By using that equation I plugged in the lengths and changed the 2.9 to micro coulombs.
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     

    Attached Files:

  2. jcsd
  3. Sep 6, 2009 #2

    Redbelly98

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    Sounds like you have the right idea. You realize that "r" is different for each pair of charges, right?

    I'm not sure what that means. Just use 2.9e-6 C, etc., for the charge values.
     
  4. Sep 7, 2009 #3
    yea i got it, i had a negative sign and it was positive. not really sure why but thanks for your help
     
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