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Circular Motion

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1. I have a quick question, and it might seem silly, in that it will probably seem obvious as soon as I hear the answer, but I'm tired and stuck and I just want to finish my homework.
The question is as follows:

A satellite orbits the Earth once every 97 minutes.

a) Calculate the angular velocity.
I've worked this out to be 1.08x10^-3. (I know it should be to 2s.f.)

b) Calculate the radius of the orbit.
This is where I get stuck. I have all of the equations in front of me, but I can't figure out how to combine them to have r in the equation without having to know the linear velocity.

I know that v=(2pi r)/T and v=wr, but when I try to equate them the r just cancels out, and I basically just don't know. It seems like I have to know v to know r, but I also have to know r to know v.

Any kind of hint is appreciated. Thanks in advance!
2. Just trying to bump this up in latest discussions because I really need to know.
3. I'd try assuming the centripetal acceleration equalled g and using
a=ω2 r
4. (Original post by Joinedup)
I'd try assuming the centripetal acceleration equalled g and using
a=ω2 r
I ended up figuring out, but thank you

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