Two concentric spheres of radii `R` and `2R` are charged. The inner sphere has a charge if `1muC` and the outer sphere has a charge of `2muC` of the same sigh. The potential is `9000 V` at a distance `3R` from the common centre. The value of R is

Options

A. `1m`
B. `2m`
C. `3m`
D. `4m`

Answer

A

Explanation

`V=1/(4piepsilon_0).q_1/(3R)+1/(4piepsilon_0).q_2/(3R)`
`=q_"net"/((4piepsilon_0)(3R))`
`:. R=(1/(4piepsilon))(q_"net")/(3V))`
`=((9xx10^9)(3xx10^-6))/((3)(9000))`
`=1m`