(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Two newly discovered planets follow circular orbits around a star in a distant part of the galaxy. The orbital speeds of the planets are determined to be 41.7 km/s and 55.5 km/s. The slower planet's orbital period is 8.04 years.(a)What is the mass of the star?(b)What is the orbital period of the faster planet, in years?

2. Relevant equations

M= r^{2}T/G

T= 2[itex]\Pi[/itex]r^{3/2}/[itex]GM_{E}\sqrt{}[/itex]

3. The attempt at a solution

I assume that the radius of the slower moving planet must be found first. Also, as for finding the period, does that same r need to be found, or is this going to be a very elaborate "plugging in the variables" type of equation?

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# Homework Help: Discovering mass of a star and orbital period of one of two planets

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