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Homework #3 solutions
•Question 2   Imagine that you're kidnapped by aliens and transported to a distant world in a different solar system. They will release you if you show your understanding of orbital dynamics. There is a planet with a period (year) 8 times longer than the planet you are on. How much further away is it from the local sun?
 
a.2 times as far.   b.4 times as far.   c.8 times as far.   d.16 times as far.   e.32 times as far.
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•Key is to use KEPLER’S 3rd Law, period squared equals radius cubed.  R = period2/3 = 82/3 = 4
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