Earth has mass 5.97×1024kg and radius 6.4×106m. A communication satellite of mass 800kg is initially in a circular parking orbit 1200km above Earth’s surface.
(i) Calculate the gravitational potential V1 at the location of the satellite in its parking orbit.
(ii) The satellite is then transferred to a higher circular orbit 3600km above the surface. Determine the gravitational potential V2 in the new orbit.
(iii) Find the work that must be done by an external agent (against gravity) to move the satellite from the parking orbit to the higher orbit, assuming the transfer is slow enough for kinetic energy changes to be neglected.