A satellite moves round the earth in a circular orbit of radius R making one revolution per day. A second satellite moving in a circular orbit, moves round the earth once in 8 days. The radius of the orbit of the second satellite is

Options

A. 8R
B. 4R
C. 2R
D. R

Answer

B

Explanation

`(T_1)/(T_2)=((r_1)/(r_2))^(3/2)rArr(1/8)^(2/3)=(r_1)/(r_2)`
`R/(r_2)=1/4rArrr_2=4R`