Calculate the orbital period of a spacecraft around the moon

AI Thread Summary
The discussion focuses on calculating the orbital period of a spacecraft around the Moon at an altitude of 100 km. The relevant formula provided is T = 2(pi)(r^3/2) / sqrt(GM), where the mass of the Moon is 7.35 x 10^22 kg and its radius is 1.74 x 10^6 m. Participants confirm that the radius for calculations should include the Moon's radius plus the altitude of 100 km. There is a request for clarification on the calculation steps and results to ensure accuracy. The conversation emphasizes collaborative problem-solving in physics.
pinkerpikachu
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1. During an Apollo lunar landing mission, the command module continued to orbit the Moon at an altitude of 100km. How long did it take to go around the Moon once?

2. T= 2(pi)(r^3/2) / root (GM)
mass of moon = 7.35 X 10^22
radius of moon= 1.74 X 10^6




3. I think that is the correct equation, and I've tried plugging all the values in. I know that the radius will have the 100km (100,000m) added on to it...right?
 
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pinkerpikachu said:
1. During an Apollo lunar landing mission, the command module continued to orbit the Moon at an altitude of 100km. How long did it take to go around the Moon once?

2. T= 2(pi)(r^3/2) / root (GM)
mass of moon = 7.35 X 10^22
radius of moon= 1.74 X 10^6

3. I think that is the correct equation, and I've tried plugging all the values in. I know that the radius will have the 100km (100,000m) added on to it...right?
Your equation is correct. What are you using for the radius of the orbit?

AM
 
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Be sure to include that the radius of the orbit is 100+ radius of the moon in km.
 
Welcome pinkerpikachu to PF forums! You will find this is a great forum for interactive discussion on all kinds of topics.

In your question, you are off to a good start. It would be useful to show us the results of your calculations (and the steps you made to get there). This will enable us to see if you are on the right track.
 
I'm working on the same problem, can you help me understand how you derived your initial equation?
 
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