Geosynchronous satellite

[aligass2004]

1. The problem statement, all variables and given/known data
http://i241.photobucket.com/albums/ff4/alg5045/MUG_co_6.jpg

A satellite that goes around the earth once every 24 hours is called a geosynchronous satellite is in an equatorial orbit, its position appears stationary with respect to a ground station, and it is known as a geostationary satellite.

Find the radius R of the orbit of a geosynchronous satellite that circles the earth. (Note that R is measured from the center of the earth, not the surface) You may use the following constants:

G=6.67*10^-11
mass of the earth = 5.98*10^24 kg
radius of the earth = 6.38*10^6 m


2. Relevant equations



3. The attempt at a solution

I have no idea how to even begin this problem.

[D H]

What is a geosynchronous satellite's orbital period? What are the relevant equations regarding orbital period?

[aligass2004]

The orbital period is 24 hours or 86400 seconds. I think the relevant equation is v = 2(pi)(r)/T.

[D H]

You aren't incorporating gravity. You need to do that.