Centripetal force does no work on an orbiting satellite. This is because work is only done when a force has a component in the direction of the displacement of the object. In the case of a satellite in orbit, the centripetal force acts perpendicular to the satellite’s direction of motion (which is tangential to its orbit). Since work requires a force to have a component in the direction of displacement, and centripetal force is always at right angles to the satellite’s motion, no work is done. The satellite’s speed and kinetic energy remain constant, as the centripetal force does not change its velocity, just its direction.