Got a doosie here, Angular acceleration, time and radius.

[GRice40]

Homework Statement

An Earth satellite moves in a circular orbit with an orbital speed of 6200 m/s. Find the time of one rotation as well as the radial acceleration of the satellite in orbit.

Homework Equations

Ac= V^2/R
mAc=mg
V= 2(pi)R/t

The Attempt at a Solution

Ok, I've gone every which way I can with this problem. I don't know how to go about it. I've drawn an FBD and the only forces I can see acting on it are the weight of the satellite and the Ac. I don't know if there is supposed to be another variable that is assumed, like the radius of the earth, or if gravity acts upon the satellite at 9.8 m/s^2 like it would on earth...I'm pretty lost here. Any advice on how to start?

 

[flyingpig]

I believe the orbital speed is the tangential speed of the satellite.

What is one rotation? (quickly, go back to your unit circle!)

 

[GRice40]

One rotation is 2(pi) radians, iirc.

 

[GRice40]

I still don't know where to go from there, it seems like I need another variable somehow...