posted by Erin .
What is the gtravitational potential energy of a 2.00e3 kg staellite that is in an orbit that has a radius of 9.90e6 m around the earth? Use gravitational potential energy=0 at r=‡ (answer=-2.01e11J)
What is the work done against gravity on the satellite in the problem #1 in lifting it into it's orbit?
What is the change in the gravitational potential energy of the satellite in the problem #1 as it is lifted from the earth's surface to its orbit?
I will be happy to critique your thinking. Remember, the satellite at Earth's surface had PE, it was not zero.