Answer to Question #292531 in Physics for ;SCJJ

Question

Imagine that a satellite weighing 2500 kg revolves around the Earth in a circular path. How much work does the Earth do on top of the satellite?

Answer 1

The gravitational forces are potential, hence the work done on closed path is always zero:

$$W=\oint {\bf F}d{\bf r}=-\oint {\nabla V}d{\bf r}=0$$