The planet mars may be considered to be an isolated sphere of diameter 6.79 × 106 m with its mass of 6.42 × 1023 kg concentrated at its centre.
A rock of mass 1.40 kg rests on the surface of Mars. For this rock,
a) i) Determine its weight
ii) Show that its gravitational potential energy is -1.77 × 107]. b) Use the information in (a) ii) to determine the speed at which the rock must leave the surface of Mars so that it will escape the gravitational attraction of the planet.