A charged spherical conductor of radius `10 cm` has potential `V` at a point distant `5 cm` from its centre. The potential at a point distant `15 cm` from the centre will be

Options

A. `3V`
B. `(3)/(2) V`
C. `(2)/(3) V`
D. `(1)/(3) V`

Answer

C

Explanation

At any point a charged conductor, potential is same as on its surface, `i.e.`
`V = (q)/(4pi in_(0) R)`, where `R = 10 cm`.
At `r = 15 cm`.
`V' = (q)/(4pi in_(0) r) = (q)/(4pi in_(0) R) xx (R )/(r ) =V xx (10)/(15) = (2V)/(3)`