Question

A thin spherical conducting shell of radius R has a charge q. Another charge Q is placed at the centre of the shell. The electrostatic potential at a point P a distance `R/2` from the centre of the shell is
A. ` (2Q)`/(4pivarepsilon_0R)`
B. (2Q)/(4pi _0R)- q/(4pi_0R)`
C. ` (2Q)`/(4pivarepsilon_0R)`
D. (2Q)/(4pi _0R)- q/(4pi_0R)`

Answer 1

Correct Answer - C
At .`P`, potential due to shell :
`V-1 = q/(4 pi varepsilon_(0) R)`
At `P`, potential due to `Q` :
`V_2=Q/(4 pi varepsilon_0R/2)`
Net potential at`R`
`V = V_1 + V_2`
`= q/(4 pi varepsilon_0 R) + (2 Q)/(4 pi varepsilon_0 R)` .