Question

A conducting sphere of radius $R$ is given a charge $Q$. The electric potential and the electric field at the centre of the sphere respectively are

• A. Zero and $ \frac{Q}{4\pi\varepsilon _0R^2} $
• B. $ \frac{Q}{4\pi \varepsilon _0R} $ and Zero
• C. $ \frac{Q}{4\pi \varepsilon _0R}$ and $\frac{Q}{4\pi \varepsilon _0R^2} $
• D. Both are Zero

Answer 1

Answer: (B)

For the conducting sphere,
Potential at the centre = Potential on the sphere
$ = \frac{1}{4 \pi \varepsilon _0} \frac{Q}{R} $
Electric field at the centre = 0