Question

The time period of a satellite in a circular orbit of radius $R$ is $T$. The period of another satellite in a circular orbit of radius $9 R$ is :

• A. 9 T
• B. 27 T
• C. 12 T
• D. 3 T

Answer 1

Answer: (B)

$T^{2} \propto R^{3}$
$\left(\frac{T'}{T}\right)^{2}=\left(\frac{9 R}{R}\right)^{3}$
$T^{'2}=T^{2} \times 9^{3}$
$T'=T \times 3^{3}$
$T'=27 \,T$