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Can someone please help me? please?

  1. Nov 16, 2009 #1
    Earth's gravitational field is 7.95 N/kg at the altitude of the space shuttle.
    What is the size of the force of attraction between a student of mass 48.9 kg and Earth?

    answer in units of N.

    please help, i don't get how to do this!

  2. jcsd
  3. Nov 16, 2009 #2


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    Homework Helper

    7.95 N/kg = 7.95 m/s². This is the value of g at the shuttle, a bit smaller than it is at the surface of the Earth.

    The force of gravity between two masses like the Earth and the student on the space shuttle is F = GMm/d² where M is the mass of the Earth and m the mass of the student. Often it is convenient to split this formula into two parts. We say F = mg and g = GM/d². It actually turns out that there really is a g field lying between the two masses. The M causes a gravitational field g around itself and the field causes the force on m. Anyway, that's all you need to do your problem!
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