Q 12-01-071JEE MainJEE Main 2023 (30 Jan, Shift 2)Easy
As shown in the figure, a point charge $Q$ is placed at the centre of conducting spherical shell of inner radius $a$ and outer radius $b$. The electric field due to charge $Q$ in three different regions $I$, $II$ and $III$ is given by ($I: r<a$, $II: a<r<b$, $III: r>b$)
Answer: (B) $E_I\ne0,\ E_{II}=0,\ E_{III}\ne0$
- Region I: the field of $Q$ is present, $E_I=\dfrac{Q}{4\pi\epsilon_0r^2}\ne0$.
- Region II: inside the conducting material the field is zero.
- Region III: charge $+Q$ appears on the outer surface, so $E_{III}=\dfrac{Q}{4\pi\epsilon_0r^2}\ne0$.
Solution by Sreeraj P, M.Sc Physics