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Homework Help: Gravitational problem

  1. Dec 12, 2007 #1
    1. The problem statement, all variables and given/known data

    Whats the earth's orbital period around the sun if mE=5.98x10^24kg , mS =2x10^30kg,
    r = 1.5x10^11


    2. Relevant equations
    T^2= kr^3


    3. The attempt at a solution

    i can figure out the period easily w/ 2 radii + 1 period
     
  2. jcsd
  3. Dec 12, 2007 #2

    Shooting Star

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    Assuming that the orbit is circular, use grav force on earth due to sun is equal to the centrpetal force. Also, T=2pi/omega.
     
  4. Dec 12, 2007 #3
    cant use omega ,,answer has to be in sec not rads :(
     
  5. Dec 12, 2007 #4

    Shooting Star

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    That's why I'd given the relation between T and omega.
     
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