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Homework Help: Need help using Coulomb's Law; finding q1 when q2>q1

  1. Jan 26, 2010 #1
    A system consists of two positive point charges, q_1 and q_2 > q_1. The total charge of the system is 64.0 \mu C, and elec each charge experiences antrostatic force of magnitude 76.0 N when the separation between them is 0.270 {\rm m}.

    Im having a little trouble determining q1, it must be simple but i just cant see it! arrgh!
     
  2. jcsd
  3. Jan 26, 2010 #2
    the equation used is coulombs law; f= k *q1*q2/ r squared
     
  4. Jan 26, 2010 #3

    kuruman

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    You have a system of two equations and two unknowns. The unknowns are q1 and q2. One equation is Coulomb's Law as you have written it in posting #2. What is the second equation?
     
  5. Jan 26, 2010 #4
    I realize i should post my work that ive done already....well i decided that both q1 and q2 cannot be equal since all other info would be irrelevant..i tried using the fundamental charge, 1.6*10^-19 as the value for q1 but that doesnt seem to fit, ive been on this problem for about an hour now but i cant seem to see the relation between the two..i apologize about my original post that didnt include my thinking process
     
  6. Jan 26, 2010 #5
    i'm not sure we were given a second equation in lecture...maybe thats why im not understanding haha
     
  7. Jan 26, 2010 #6

    kuruman

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    The second equation is stated in the problem. Read the problem statement carefully.
     
  8. Jan 26, 2010 #7
    I just got it man, thank you!
     
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