Satellite and gravitational force

AI Thread Summary
A 500 kg satellite in a circular orbit experiences a gravitational force of 3000 N. The initial attempt to find the radius of the orbit using the formula g = GM/r^2 resulted in an implausible radius of 3.33 x 10^-6 m. The error was identified as neglecting the mass of the satellite in the gravitational force equation. The correct formula for gravitational force is F_G = GMm/r^2, which includes the satellite's mass. This discussion highlights the importance of correctly applying gravitational equations in orbital mechanics.
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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?
 
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Think about your answer for a second... does 10^-6m make any physical sense?
 
not at all...where did i go wrong?
 
Your equation is missing a term for the mass of the satellite:

F_{G} = \frac{GMm}{r^{2}}
 
thanks a lot!
 
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