A satellite orbits the earth at a height of 500 km from its surface. Compute its:
(a) kinetic energy
(b) potential energy
(c) total energy.
Mass of the satellite = 300 kg,
Mass of the earth = 60 x 1024kg,
Radius of the earth = 6.4 x 106m
G = 6.67 x 10-11 Nm2/kg2.
Will your answers alter if the earth shrinks suddenly to half of its present size?
We have,
Mass of the satellit, m = 300 kg
Mass of the Earth, M= 6.0 x 1024kg
Radius of Earth, R = 6.4 x 106m
Gravitational constant, G = 6.67 x 10-11 Nm2/kg2
(a) Kinetic energy of satellite is,
(b) Potential energy of satellite is, 
(c)Total energy of satellite is,
E = K.E. + P.E.
= 8.7 x 109 -17.4 x 109
= -8.7 x 109J
(d) If the earth shrinks to half its size without changing its mass, the answers will remain the same.
