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Homework Help: Gravitation Problem

  1. Dec 12, 2007 #1
    Gravitation Problem :(

    Find the point between earth and the sun at which an object can be placed so that the net gravitational force exerted by earth and the sun on an object is zero.

    Earth's mass: 5.98x10^24 kg
    Earth's radius: 6.38x10^6 m

    Sun's mass: 1.991x10^30 kg
    Sun's radius: 6.96x10^8 m

    I know I have to use the equation for gravitational force:

    So at this point I'm lost. Do I make up a mass for the object and figure out the force for earth and the sun separately? Do I put the values for the sun and earth into one equation and set the force equal to zero??? Any help would be greatly appreciated :D
  2. jcsd
  3. Dec 12, 2007 #2
    take any arbitrary mass m and go from there.
  4. Dec 12, 2007 #3
    So I found the sun and the earth's respective gravitational forces...
    How would I go about finding the point where they equal zero?
  5. Dec 12, 2007 #4

    Shooting Star

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    Homework Helper

    Show us your calculations.
  6. May 18, 2010 #5
    Re: Gravitation Problem :(

    this question is complete, for this you should must knew about the distance between sun and earth...
    as this distance keeps changes therfore first notify the exact distance for which you want the answer.ok
    well according to me ans should be

    where y means distance between earth and sun

    and x means distance of object from sun...
    therefore after putting value of "y" you will get value of "x" and after it you can easily find distance between object and earth too
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