Two satellites `A` and `B` of the same mass are revolving around the earth in the concentric circular orbits such that the distance of satellite `B` from the centre of the earth is thrice as compared to the distance of the satellite `A` from the centre of the earth. The ratio of the centripetal force acting on `B` as compared to that on `A` is

Options

A. 3
B. `1//sqrt3`
C. `1//3`
D. `1//9`

Answer

d

Explanation

`(F_(B))/(F_(A))=(GMm)/(r_(B)^(2))xx(r_(A)^(2))/(GMm)=((r_(A))/(r_(B)))^(2)`
`=((r_(A))/(3r_(A)))^(2)=(1)/(9).`