Question
Two satellites of equal masses are orbiting the earth in different radii such that time period of revolutions are T and 2T. What is the ratio of moment of inertia of two satellites about the centre of the earth respectively?
Solution
Let R1 and R2 be the radii of orbits of satellites having time period T and 2T.


According to Kepler's third law,
T2 ∝ R3
Ratio of the moment of inertia of first to second satellite is,