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Homework Help: What is the magnitude of the force of particles?

  1. Jan 18, 2010 #1
    1. The problem statement, all variables and given/known data

    Two charged particles exert an electrostatic force of 10 N. What will be the magnitude of the force if q1 is three times q2 and the distance between particles is increased to five times the original distance?


    2. Relevant equations



    3. The attempt at a solution


    I don't have the slightest idea as to how to answer this. someone please help?
     
  2. jcsd
  3. Jan 18, 2010 #2

    tiny-tim

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    Hi haengbon! :wink:

    Call the original distance x.

    What equations do you know that might help? :smile:
     
  4. Feb 8, 2010 #3
    thank you for replying! :smile:

    I honestly don't know any equations for it :(
     
  5. Feb 8, 2010 #4

    chemisttree

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    Have you heard of Coulomb's Law? Good place to start.
     
  6. Feb 13, 2010 #5
    is it the F=k(q1q2)/r2?

    so... k=9x10^9 and F=10...

    that's all I understand from it :(
     
  7. Feb 13, 2010 #6

    tiny-tim

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    Hi haengbon! :smile:

    (try using the X2 and X2 tags just above the Reply box :wink:)
    Yes, that's the force of one charged particle on the other at distance r.

    So how much will the magnitude, F, of the force be if the distance between the same particles is increased to five times r? :smile:
     
  8. Feb 14, 2010 #7
    so...it'll be

    F= K(Q1Q2)/r
    10= 9x109(Q1Q2)/ r(5) ?

    I really appreciate your guidance through the whole problem ^^
     
  9. Feb 15, 2010 #8

    tiny-tim

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    Hi haengbon! :smile:

    (just got up :zzz: …)
    i] what happened to r2 ? :redface:

    ii] you're not reading the question carefully …

    what is 10?
     
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