Calculating a Spy Satellite's Orbit Parameters

[Jtappan]

Homework Statement

A spy satellite is in circular orbit around Earth. It makes one revolution in 6.00 hours.

(a) How high above Earth's surface is the satellite?
________ km
(b) What is the satellite's acceleration?
________ m/s2

Homework Equations

GMm/r^2 = m(v^2/r)

The Attempt at a Solution

I don't understand how you find these answers if you don't have the mass of the satelite.

 

[learningphysics]

masses cancel...

GMm/r^2 = m(v^2/r)

you can cancel m from both sides

GM/r^2 = v^2/r

you need to look up M the mass of the earth...

Get another equation in terms of v and r (use the 6.00hr)

Then you can solve for r and v, since you have 2 equations with 2 unknowns.