Question

A 5000-kg spacecraft is in a circular orbit 2000 km above the surface of mars. how much work must the spacecraft engines perform to move the spacecraft to a circular orbit that is 4000 km above the surface?

Answer 1

The spacecraft is orbiting at 2000 Km. The engine has to put it on 4000 km altitude, therefore the engine has to push it into another 2000 km, so that it will attain the 4000 km altitude.

Given. Gravitational pull of planet Mars g = 3.71 m/s²

            Mass of the spacecraft m = 5000 kg

Formula: W = fd   F = mg    

               W = mgh

               W = (5000 Kg)(3. 71 m/s²)(2 x 10⁶m)

               W = 3.71 x 10¹⁰ J