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Homework Help: Newtons law of gravitation

  1. Sep 5, 2004 #1
    I'm stuck on the following question:

    Newton's law of universal gravitation is represented by the following equation.
    F = GMm/r2

    Here F is the magnitude of the gravitational force exerted by one small object on another, M and m are the masses of the objects, and r is a distance. Force has the SI units kg · m/s2. What are the SI units of the proportionality constant G?

    Not sure of what to do, please help
  2. jcsd
  3. Sep 5, 2004 #2
    Just solve for G:

    kg*m/s^2 = G*kg*kg/m^2

    What you can do with numbers can also be done with units...
  4. Sep 6, 2004 #3
    I solved for G and I get (m/s^2 / kg/m^2) = G, however, its not correct.
  5. Sep 6, 2004 #4
    uhh... you didn't even simplify it. so guess what you have to do....
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