JEE MainPhysicsGravitation
Two identical satellites, A and B, are revolving in circular orbits around a planet. If the orbital angular momentum of satellite A is twice the orbital angular momentum of satellite B, the ratio of their time periods of revolution ( T_A T_B ) is :
Options
- A2 2
- B4
- C2
- D8
Correct answer
D. 8
Step-by-step solution
The orbital angular momentum of a satellite of mass m in a circular orbit of radius r is: L = mvr The orbital speed is given by v = GM r , where M is the mass of the planet. Substituting v into the expression for L : L = m GM r r = m GMr Since m , G , and M are constants, we have: L r r L^2 According to Kepler's Third Law, the time period T is related to the orbital radius r as: T^2 r^3 T r^ 3/2 Substituting r L^2 into the relation for T : T (L^2)^ 3/2 T L^3 Therefore, the ratio of the time periods is: T_A T_B = (