Question

Two satellites $S_1$ and $S_2$ are revolving around the earth in coplanar concentric orbits in the opposite sense. At $t=0$, the positions of satellites are shown in the diagram. The periods of $S_1$ and $S_2$ are $4$h and $24$h, respectively. The radius of orbit of $S_1$ is $1.28\times {10}^4$km. For this situation, mark the correct statement(s).

• A. The angular velocity of $S_2$ as observed by $S_1$ at $t=12$h is $0.468\pi$rad $s^{-1}$
• B. The two satellites are closest to each other for the first time at $t=12$h and then after every $24$h they are closest to each other
• C. The orbital velocity of $S_1$ is $0.64\pi \times {10}^4$km
• D. The velocity of $S_1$ relative to $S_2$ is continuously changing in magnetic and direction both

Answer 1

Answer: (A), (B), (C), (D)

The correct options are
A The angular velocity of $S_2$ as observed by $S_1$ at $t=12$h is $0.468\pi$rad $s^{-1}$
B The two satellites are closest to each other for the first time at $t=12$h and then after every $24$h they are closest to each other
C The orbital velocity of $S_1$ is $0.64\pi \times {10}^4$km
D The velocity of $S_1$ relative to $S_2$ is continuously changing in magnetic and direction both