The spherical shell has radius r. The potential difference V is between centre to distnnce 3r. The electric field at a distance 3r will be ........

Options

A. `(V)/(6r)`
B. `(V)/(4r)`
C. `(V)/(3r)`
D. `(V)/(2r)`

Explanation

The potential at the centre of spherical shell `V_(1)=(kq)/(r)` and potential `V_(2)` between centre to distance `2r = V_(2) =(kq)/(3r)`
`:. V= V_(1)-V_(2)`
`= kq [(1)/(r) -(1)/(3r)]`
`= kq[(2)/(3r)]`
`:. (3Vr)/(2) = kq`

Now `E= (kq)/((3r)^(2))=(3Vr)/(2)xx(1)/(9r^(2))=(V)/(6r)`