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Calculating orbital speed/period

  1. Apr 11, 2010 #1
    1. The problem statement, all variables and given/known data
    The mass of the sun is 2x10^30kg and the planet Jupiter averages an orbital distanceof 5.2 AU. Calculate the orbital speed (in mph) and orbital period (in earth years) of Jupiter relative to the Sun: One AU is one Astronomical Unit which is the average earth-sun distance... 1 AU = 1.5x10^11m.

    2. Relevant equations

    Vorb= sqrt(GM/r)


    r = (1.5x10^11m)(5.2) = 7.8x10^11m
    G = 6.67x10^-11 Nm^2/kg^2
    M= 2x10^20kg

    3. The attempt at a solution

    I plugged in the numbers and ended up with...

    Vorb = 4.39 x 10^4 m/s = 98199.91 mph
    T= 374751912s = 11.88 years

    Does this look right?
  2. jcsd
  3. Apr 11, 2010 #2


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    Gold Member

    Why don't you look up the orbital period of Jupiter and see for yourself?
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