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

Options

A. `(2Q)/(4piepsilon_(0)R)-(2q)/(4 pi epsilon_(0)R)`
B. `(2Q)/(4pi epsilon_(0)R)+q/(4pi epsilon_(0)R)`
C. `((q+Q))/(4pi epsilon_(0))2/R`
D. `(2Q)/(4 pi epsilon_(0)R)`

Answer

B

Explanation

Potential due to point charge
`V_(1)=Q/(4pi epsilon_(0)(R/2))`
Potential due to shell at inside point
`V_(2)=V_(R/2)=V_("surface")`
`V_(2)=q/(4p epsilon_(0)R)`
`V_("total")=(2Q)/(4 pi epsilon_(0))+q/(4pi epsilon_(0)R)`