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Homework Help: Finding the orbital height of a satellite

  1. Feb 2, 2010 #1
    1. The problem statement, all variables and given/known data
    I have to find the orbital height of a satellite with a specific g force (ie. the acceleration due to gravity). g=5.7(ms)2


    2. Relevant equations

    So far I have been using the equation g=Gm/(r+h)2 to find the acceleration due to gravity, where G= gravitational constant, m=mass of the Earth ,r=radius of the earth and h= the orbital height from the Earth

    except now I am given a specific g force and have been asked to find the height.


    3. The attempt at a solution
     
  2. jcsd
  3. Feb 2, 2010 #2

    rock.freak667

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    Homework Helper

    Not sure what is puzzling you.

    g=GM/(r+h)2 and they give you g=5.7 m/s2

    ∴5.7=GM/(R+h)2

    G,M and R are all known, cross multiply and then do some algebra to get 'h'.
     
  4. Feb 2, 2010 #3
    Cheers,
    bit slow on the uptake today, but that was all I wanted to know.
     
  5. Feb 3, 2010 #4
    Back again, moving the equation around dosn't help because the h is inside the brackets, along with the Earth's radius (r+h). What am I missing?
     
  6. Feb 3, 2010 #5

    rock.freak667

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    When you reach (R+h)2=A, take the square root of both sides.
     
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