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

A satellite is to be placed in orbit about the earth at an altitude of 1.6 x 10^{6}m. What will be its period of motion?

The answer is 7.2x 10^{3}s

2. The attempt at a solution

Using kelper's third law.

R^{3}/ T^{2}= R^{3}/ T^{2}

Radius of satellite: 6.38 x 10^{6}+ 1.6 x 10^{6 }= 7.98 x 10^{6}

Radius of earth: 6.38 x 10^{6}

Period of satellite: ?

Period of earth: 3.16 x 10^{7}

When I plugged these numbers in, I get 4.42 x 10^{7}s

I've used the formula before without any problems, so that's not the issue.

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

Determine the radius of a satellite's synchronous orbit around Uranus. Your very friendly, local astronomer informs you that uranus' moon, Miranda, has an average radius of revolution of 1.24 x 10^{5}km with a period of revolution of 1.4 earth days.

The answer is 5.8 x 10^{7}m

4. The attempt at a solution

Same thing as above, I used kelper's third law.

R^{3}/ T^{2}= R^{3}/ T^{2}

Radius of Miranda: 1.24 x 10^{5}

Radius of satellite: ?

Period of miranda: 1.4 days * 3600 * 24 = 120960s

Period of satellite: (I'm assuming this is period of Uranus?) 2.66 x 10^{9}

I plugged these numbers in and I got 9.73 x 10^{7}m

Thank you in advance!!~~ :)

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# Homework Help: A couple of gravitational problems (kelper's third law)

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