Question

An isolated sphere of radius $R$ contains uniform volume distribution of positive charge. Which of the curve shown below, correctly illustrate s the dependence of the magnitude of the electric field of the sphere as a function of the distance $r$ from its centre?

• A. I
• B. II
• C. III
• D. IV

Answer 1

Answer: (B)

Electric field $E$ of a solid sphere varies with distance from centre $r$ as
$E=\{\begin{array}{ll}{C}_1\cdot r,& r<0\\ \frac{C_2}{r^2},& r\ge 0\end{array}$
where, $C_1$ and $C_2$ are constants. So, correct graph of $E$ versus $r$ is