Two satellites of earth `S_(1)` and `S_(2)` are moving in the same orbit. The mass of `S_(1)` is four times the mass of `S_(2)`. Which one of the following statements is true?

Options

A. The potential energies of earth and satellite in the two cases are equal
B. `S_(1)` and `S_(2)` are moving with same speed
C. The kinetic energies of two satellites are equal
D. The time period of `S_(1)` is four times that of `S_(2)`

Answer

B

Explanation

Orbital speed is `v = sqrt((GM)/(a))`
where M is mass of planet. Hence both satellites must have same speed. Hence option (b) is correct. Time periods are same. K.E. and P.E. of two satellites cannot be equal due to different masses.