A satellite is launched into a circular orbit of radius R around the earth. A second satellite is launched into an orbit of radius 4R. The ratio of their respective periods is

Options

A. `4 : 1`
B. `1 : 8`
C. `8 : 1`
D. `1 : 4`

Answer

B

Explanation

We have `T^(2) prop R^(3)`
`R_(1) = r and R_(2) = 4r`
`(T_(1)^(2))/(T_(2)^(2)) = ((r)^(3))/((4r)^(3))`
`(T_(1))/(T_(2)) = (1)/(8)`