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Homework Help: Gravitational related problem

  1. Oct 30, 2005 #1
    Last edited by a moderator: Apr 21, 2017
  2. jcsd
  3. Oct 30, 2005 #2

    Tide

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    You know what r is in both cases so just use the formula to express F and F' for both cases and compare the two results.
     
  4. Oct 30, 2005 #3
    I still don't understand...where does R come into the formula?? :uhh:
     
  5. Oct 30, 2005 #4

    Tide

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    r is the distance between the center of the Earth and the object in question. That is the symbol people usually use but I just noticed the picture you showed uses "d" to represent that distance so r is the same as your d.
     
  6. Oct 30, 2005 #5
    Ok please bear with me if I sound dumb...never taken physics before so I'm finding it realli difficult :cry:
    So do I have to find m1 and m2? And for G I've been given an approximation for it, and I dunno if I'm suppose to use it :confused:
     
  7. Oct 30, 2005 #6

    Tide

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    Assuming that neither the mass of the plane nor of the Earth change then they both cancel out - along with G! They made it really convenient for you. :)
     
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