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Homework Help: Kelper Problems

  1. Nov 8, 2005 #1
    Here's the problem:

    Phobos and Deimos 2 satalites of mars, ahve orbits with average radii of 9380km and 23500km respectivly.

    The period of Phobos is .319 earth days. Whats is the period of Demos?

    I ahve it set up like this:


    and i know (Ta\Tb)sq'ed =(Ra\Rb)cubed. Am I right in doing this? How do I choose who is A and who is B?
  2. jcsd
  3. Nov 9, 2005 #2


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    Your approach is right. Choose them however you like. As long as you're consistent, it will be fine.
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