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Homework Help: Gravity on mass on earth's surface vs sun-earth gravity

  1. Apr 27, 2005 #1
    Q:
    A mass of 5.000 kg is sitting on the Earth's surface directly under the sun during a solar eclipse. The sun exerts a gravitational force with magnitude Fs on the mass. The moon's gravitational force on the mass has magnitude Fm. Calculate the ratio Fs / Fm.

    This problem is really frustrating me. For the object, wouldnt Fm be mg = 5*9.8?

    Then wouldnt the Fs be (mass of the sun)(mass of earth)/R^2 ?

    So wouldnt it be the Fs divided by Fm? Please help!?!?!
     
  2. jcsd
  3. Apr 27, 2005 #2

    OlderDan

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    You are being asked to calculate the ratio of the forces of attraction to the sun and to the moon for a mass that is at the surface of the earth. You are not asked for the force of attraction to the earth.
     
  4. Apr 27, 2005 #3
    HAH wow i'm embarassed... thanks :blushing:
     
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