Question

Two satellites A and B go round a planet P in circular orbits having radil 4R and R respectively. If the speed of the satellite A is 3V, the speed of the satellite B will be

• A. $12V$
• B. $6V$
• C. $\frac{3}{2}V$
• D. $\frac{3}{2}V$

Answer 1

The correct option is B

$6V$

Orbital velocity of satellite $v=\sqrt{\frac{GM}{r}}\therefore v\propto \frac{1}{\sqrt{r}}\Rightarrow \frac{V_A}{V_B}=\sqrt{\frac{r_A}{r_B}}\Rightarrow \frac{V_B}{3V}=\sqrt{\frac{4R}{R}}\Rightarrow V_B=6V$