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Homework Help: Satellite (Gravitation) Question

  1. Nov 19, 2006 #1
    A satellite has a orbital period of 5760s around earth. What is the orbital radius?

    I'm not sure how I can do this without the velocity or acceleration.

    Thanks,
     
  2. jcsd
  3. Nov 19, 2006 #2
    Is no other information provided in the question?
     
  4. Nov 19, 2006 #3
    no other information,
    however, part of the question might have been cut off
     
  5. Nov 19, 2006 #4
    EDIt: Never mind...
     
    Last edited: Nov 19, 2006
  6. Nov 19, 2006 #5

    nrqed

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    I assume they mean that the orbit is circular.

    Then simply use
    [tex] P = { 2 \pi R \over v} [/tex]

    and [tex] m { v^2 \over R} = G { m M \over R^2} [/tex]
    where M is the mass of the Earth and m is the mass of the satellite. Then you have two equations for two unknowns: R and v. Which you can then solve.

    Patrick
     
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