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 $\frac{R}{2}$ from the centre of the shell is

• A. $\frac{(q+Q)}{4 \pi \varepsilon_{0}} \frac{2}{R}$
• B. $\frac{2 Q}{4 \pi \varepsilon_{0} R}$
• C. $\frac{2 Q}{4 \pi \varepsilon_{0} R}-\frac{2 q}{4 \pi \varepsilon_{0} R}$
• D. $\frac{2 Q}{4 \pi \varepsilon_{0} R}+\frac{q}{4 \pi \varepsilon_{0} R}$

Answer 1

Answer: (D)

Electric potential at $P$,

$V=\frac{k \cdot Q}{R / 2} +\frac{k \cdot q}{R}$
$=\frac{2 Q}{4 \pi \varepsilon_{0} R}+\frac{q}{4 \pi \varepsilon_{0} R}$