Q.
The adjacent diagram shows a charge $+ Q$ held on an insulating support $S$ and enclosed by a hollow spherical conductor. $O$ represents the centre of the spherical conductor and $P$ is a point such that $OP = x$ and $SP = r$
The electric field at point $P$ will be
A) $\frac{Q}{4\pi\varepsilon_{0}x^{2}}$
B) $\frac{Q}{4\pi\varepsilon_{0}r^{2}}$
C) 0
D) None of the above
Explanation
(a) According to Gauss’s theorem
[image:1_image209.emf]
$\oint_{}^{}{\overrightarrow{E}.d\overrightarrow{s}} = \frac{1}{\varepsilon_{0}}Q_{enclosed}$
$E.4\pi x^{2} = \frac{Q}{\varepsilon_{0}}$
$E = \frac{Q}{4\pi\varepsilon_{0}x^{2}}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.