Because of the friction between the water in oceans with the earth's surface, the rotational kinetic energy of the earth is continuously decreasing. If the earth's angular speed decreases by 0.0016 rad/day in 100 years, find the average torque of the friction on the earth. Radius of the earth is 6400 km and its mass is 6.0 ×1024kg.
A satellite of mass 1000 kg is suposed to orbit the earth at a height of 2000 km above the earth 's surface. Find (a) its speed in the orbit, (b) its kinetic energy, (c) the potential energy of the earth - satellite system and (d) its time period. Mass of the earth =6×1024 kg.