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Homework Help: Newton’s law of universal gravitation

  1. Jan 20, 2010 #1
    20. According to Newton’s law of universal gravitation, the force of attraction between any
    two masses is related directly to the
    A. velocity of the two masses
    B. product of the two masses
    C. distance between the masses
    D. sum of the masses
    ( I wasnt sure for this question so I had to guess)
    Is this the answer if it is what is the logic behind it
  2. jcsd
  3. Jan 20, 2010 #2


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    Note the word direct(ly proportional), as opposed to inverse(ly proportional).

    What happens to the force if you increase (let's say: double) one of the masses? What happens if you increase (say: double) the distance?

    Does it get larger or smaller?
  4. Jan 20, 2010 #3
    So the answer would be B. is this correct?
  5. Jan 20, 2010 #4
    but try and understand why. Write the equation out and look at how all the variables relate to each other an like compuchip said what happens to the force if you double one of the masses etc.
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