# A satellite in orbit

1. Dec 10, 2004

### triden

I can't decide what to do with this question. I am studying for a final. I converted 24 hours to seconds and tried using the Fg = -gmm/r but I dont think thats going to work...

Last edited by a moderator: May 1, 2017
2. Dec 10, 2004

### theFuture

You're on the right track. Think about circular motion, too.

3. Dec 10, 2004

### triden

ok I think im getting it.

r*(omega)^2 = GM/r^2

then i can cancel the R's to get

Omega^2 = GM/r ?

4. Dec 10, 2004

### dextercioby

5. Dec 11, 2004

### Gamma

you mean omega^2 = GM/r^3

6. Dec 11, 2004

### frankR

That's one of my favorite problems.

I think the answer is about 24,000mi. Don't forget to subtract the radius of the earth. I always forget to do that!

7. Dec 11, 2004

### saltrock

i Think radius should be (R+r) and use F=GMm/(R+r)^2

8. Dec 11, 2004

### dextercioby

Why complicate?Use "r" as your length variable (the radius of the trajectory)and then,once u got the result,subtract the mean radius of the Earth which is round about 6371km.