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Homework Help: Please help me, really frustrated, question is due @ 11:59 tonight

  1. Nov 15, 2005 #1
    hi, thanks for helping me.

    heres the question

    Suppose the moon had a net negative charge equal to -q and Earth had a net positive charge equal to +10q. What value of q would yield the same magnitude force that you now attribute to gravity?

    (answer in coulombs) I have it on a thing called webassign, and you can only have 15 tries...... i used 14. here are my wrong attempts:
    1.6e-19
    1.6e-18
    -1.6e-18
    -1.6e-20
    1.6e-20
    1.6e18
    8.99e10
    -8.99e10
    .1
    -.1
    8.99e9
    -8.99e9
    -8.99e8
    -10
     
    Last edited: Nov 15, 2005
  2. jcsd
  3. Nov 15, 2005 #2

    Pengwuino

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    Gold Member

  4. Nov 16, 2005 #3

    andrevdh

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    Homework Helper

    The gravitational attraction must equal the electrostatic attraction
    [tex]\frac{Gm_em_m}{r^2} \ = \ \frac{kq_1q_2}{r^2}[/tex]
     
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