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Homework Help: Circular Orbits

  1. Oct 12, 2007 #1
    1. The problem statement, all variables and given/known data
    A satellite is in a circular orbit about the earth (M = 5.98 x 1024 kg). The period of the satellite is 7.12 x 104 s. What is the speed at which the satellite travels?

    2. The attempt at a solution
    I used the equation:

    http://img171.imageshack.us/img171/7176/math062gg0.gif [Broken]

    Re-arranged it to isolate r:

    http://img74.imageshack.us/img74/9274/math065rr5.gif [Broken]

    After I got radii, i solved for velocity:

    http://img171.imageshack.us/img171/3975/math053pd6.gif [Broken]

    My answer: 1.26x10^7 m/s
    Teacher: Incorrect

    Note: The numbers in the equations are not the actual ones i used.
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Oct 12, 2007 #2


    User Avatar
    Homework Helper

    The equations seem right to me. Seems like something went wrong when plugging in the numbers. What are the actual numbers you used?
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