In the figure the blue planet has a period of 1 year and an average distance from the sun of 1.73 x 1011 meters. If the average distance from the sun for the red planet is 1.39 x 1011 meters, what is its period to the nearest hundredth of a year?(adsbygoogle = window.adsbygoogle || []).push({});

So I thought maybe they through in the information on the blue planet to confuse me, so disregarding that information, I used the formula:

T=(2pi/square root of GM)*r^3/2

where G=6.67e-11 and M is the mass of the sun=2.0e30kg

Unfortunately, this isn't correct, and I don't see where I am supposed to incorporate the information about the blue planet with the red planet.

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# Homework Help: Period of a planet.

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