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Homework Help: Distance from sun to earth= 1.5 x10^11m

  1. Dec 18, 2008 #1
    Please help!!!

    1. The problem statement, all variables and given/known data
    Find the point between Earth and the Sun at which an object an be placed so that the net gravitatinal force exerted by Earth an the sun on this object is zero.

    Me=5.98 x 10^24kg
    Ms=2 x 10^30kg
    Distance from sun to earth= 1.5 x10^11m

    2. Relevant equations

    F=Gm1m2/r^2 --> not sure if this is right?

    3. The attempt at a solution

    So I tried to manipulate the situation and thought I could do:
    When x equals the distance from the sun.

    (G(Ms)) / x^2 = (G(Me))/ (d-x)^2

    When I plugged in the numbers though I got 1.49x10^11m as my answer. I don't feel like this is right because it's pretty much the full distance between them. Is this not the way to do it, and if not how do I go about doig this problem?
  2. jcsd
  3. Dec 18, 2008 #2
    Re: Please help!!!

    I have not done this one in a while, but I believe that you may need to take the radii of the bodies into account. Since in that formula for Gravitational force, r is the distance between the centers.
  4. Dec 18, 2008 #3


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