(adsbygoogle = window.adsbygoogle || []).push({}); [SOLVED] need help with keplers 3rd law of periods problem

1. The problem statement, all variables and given/known data

A 20 kg satellite has a circular orbit with a period of 2.6 h and a radius of 9.4E6 m around a planet of unknown mass. If the magnitude of the gravitational acceleration on the surface of the planet is 8.6 m/s2, what is the radius of the planet?

2. Relevant equations

T^2=((4pi^2)/(GM))r^3

a gravity=(GM)/r^2

3. The attempt at a solution

I used the law of periods to find the mass and then used the second equation to find the radius of the planet but I got a really small number

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# Homework Help: Need help with keplers 3rd law of periods problem

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