# Satellite and gravitational force

1. Jul 20, 2011

### fa08ti

a 500 kg satellite experiences a gravitational force of 3000 N, while moving in a circular orbit around the earth.
a: find the radius of the circular orbit
b: find the speed of the satellite
c: find the period of the orbit

attempt

a:
g= GM/r^2
r=sqrt(GM/g)
r= 3.33 x 10^-6 m

am i right?

2. Jul 20, 2011

### Clever-Name

3. Jul 20, 2011

### fa08ti

not at all...where did i go wrong?

4. Jul 20, 2011

### Clever-Name

Your equation is missing a term for the mass of the satellite:

$$F_{G} = \frac{GMm}{r^{2}}$$

5. Jul 20, 2011

### fa08ti

thanks a lot!