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Homework Help: At what distance from the Earth and the moon have zero net force?

  1. May 29, 2010 #1
    1. The problem statement, all variables and given/known data

    At what distance from the Earth will a spacecraft traveling directly from the Earth to the Moon experience zero net force because the Earth and Moon pull with equal and opposite forces?

    2. Relevant equations

    GM(earth)/(R-d)^2=GM(moon)/d^2

    3. The attempt at a solution
    Me/Mm=81.3
    root 81.3=(R-d)/d

    I have no idea how to figure out the rest of the question. Please help.
     
  2. jcsd
  3. May 29, 2010 #2

    rock.freak667

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    Homework Helper

    (a-b)/c = a/c - b/c

    use this and solve
     
  4. May 29, 2010 #3

    rock.freak667

    User Avatar
    Homework Helper

    (a-b)/c = a/c - b/c

    use this and solve
     
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