The magnitudes of the gravitational fields at distances `r_1` and `r_2` from the centre of a uniform sphere of radius R and mass M are `F_1` and `F_2` respectively then
(a)`F_1/F_2=r_1/r_2` if `r_1 lt R` and `r_2 lt R`
(b)`F_1/F_2=(r_2/r_1)^2` if `r_1 gt R` and `r_2 gt R`
(c)`F_1/F_2=r_1/r_2` if `r_1 gt R` and `r_2 gt R`
(d)`F_1/F_2=(r_1/r_2)^2` if `r_1 lt R` and `r_2 lt R`

Options

A. only a and b are true
B. only b and c are true
C. only a,b and d are true
D. all are true

Answer

A