Question

8.
A satellite doesn't need any energy to revolve
earth. Why?​

Answer 1

Answer:

because the satellite is in free falling state and no energy is consumed in free falling

Answer 2

Satellites do need energy in order to get to the point where they can orbit, but do not need additionally energy when they get there for a good reason. As I'm sure you're aware, space does not have any atmosphere. ... The air molecules hit the molecules of the ball, taking away energy and slowing the ball down to a stop.