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Homework Help: Satellite Gravitation

  1. Apr 20, 2008 #1
    1. The problem statement, all variables and given/known data
    A 500 kg satellite is in a circular orbit at an altitude of 500km above the Earth's surface. Because of air friction, the satellite eventually falls to the Earth's surface where it hits the ground with a speed of 2000 m/s. How much energy was transformed to internal energy by means of friction.

    3. The attempt at a solution

    Ki + Ui = Kf + Uf loss

    [tex]-\frac{\frac{1}{2}GM_SM_E}{Ri} = \frac{1}{2}M_SV_f^2 - \frac{\frac{1}{2}GM_SM_E}{Rf}+ loss[/tex]

    [tex]-\frac{\frac{1}{2}(6.67e-11)(500)(5.98e24)}{6.37e6 + 500,000} - \frac{1}{2}(500)(2,000)^2 +\frac{\frac{1}{2}(6.67e-11)(500)(5.98e24)}{6.37e6} = loss[/tex]

    Is this how to go about this problem, or did I miss a concept at the beginning? thanks
    Last edited: Apr 20, 2008
  2. jcsd
  3. Apr 20, 2008 #2
    Is this the right process?
  4. Apr 21, 2008 #3


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    Homework Helper

    Hi Sheneron,

    I don't believe the factor of 1/2 should be in your expression for Uf.
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