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Acceleration of oneself to the moon

  1. Sep 21, 2009 #1
    1. The problem statement, all variables and given/known data
    F=GmM/r^2


    2. Relevant equations
    mass of self=109kg
    mass of moon=7.36x10^22kg
    r=384,403,000m
    gravity of moon=1.63m/s^2



    3. The attempt at a solution
    F=((1.63m/s^2)(109kg)(7.36x10^22kg))/(384,403,000)^3

    Am I doing this correctly?
     
  2. jcsd
  3. Sep 21, 2009 #2

    rock.freak667

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    What are you trying to find exactly?

    The force between you and the moon?
     
  4. Sep 21, 2009 #3

    Janus

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    No. The G in the formula you are using is the gravitational constant of the universe, not the acceleration due to gravity on the Moon.
     
  5. Sep 21, 2009 #4
    Yes, or also said the attraction between me and the moon
     
  6. Sep 21, 2009 #5
    Then what is the appropriate G?
     
  7. Sep 21, 2009 #6
    I cannot find a different value for G
     
  8. Sep 21, 2009 #7

    rock.freak667

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    G = universal gravitational constant = 6.67x10-27 m3 kg-1 s-1
     
  9. Sep 21, 2009 #8
    Why is it not the gravitational force of the moon?
     
  10. Sep 21, 2009 #9

    rock.freak667

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    g is acceleration due to gravity given as F/m (on the moon in your case works out as 1.63m/s2)

    But in the formula

    [tex]F=G \frac{m_1 m_2}{r^2}[/tex]


    G is universal gravitational constant.
     
  11. Sep 22, 2009 #10

    Janus

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    The value you are using is the acceleration due to gravity on the Moon, which is a different quanity. It can be found by

    [tex]g = \frac{GM}{r^2}[/tex]

    You cannot use "g" in the formula you had instead of "G", as, for one reason, the units don't work out.

    in your attempt at a solution you have :

    [tex]\frac{\frac{m}{s^2} (kg)(kg)}{m^2} [/tex]

    which reduces to

    [tex]\frac{kg^2}{s^2 m}[/tex]

    while the force, which you are trying to find, is measured in

    [tex]\frac{kg m}{s^2}[/tex]
     
  12. Sep 22, 2009 #11
    Hello thomas as others have pointed out you are getting G mixed up with g.In the question you are not given the value of G(although it is easy to look this up) so I assume that the intention was for you to use a different equation.In fact if it is the acceleration you want to find, instead of the weight, you do not need an equation at all.Can I suggest that you look up the meaning of g and if you get stuck come back here.
     
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