Question

# How much work is required to lift a 800-kg satellite to an altitude of 1⋅10^6 m above the surface of the earth?

The gravitational force is F=GMm/r^2, where M is the mass of the earth, m is the mass of the satellite, and r is the distance between them. The radius of the earth is 6.4⋅10^6 m, its mass is 6⋅10^24 kg, and in these units the gravitational constant, G, is 6.67⋅10^−11.