A metallic spherical shell has an inner radius $R_1$ and outer radius $R_2$. A charge $Q$ is placed at the centre of the spherical cavity. What will be surface charge density on the inner surface
A$\frac{Q}{{4\pi R_1^2}}$
B$ - \frac{Q}{{4\pi R_1^2}}$
C$\frac{Q}{{4\pi R_2^2}}$
D$ - \frac{Q}{{4\pi R_2^2}}$
Medium
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B$ - \frac{Q}{{4\pi R_1^2}}$
b A charge $\mathrm{Q}$ is placed at the centre of the spherical cavity. So, the charge induced at the inner surface of the sphere will be -Q and at outer surface of the sphere is $+Q$.
The surface charge density on the inner surface $\sigma_{1}=\frac{\text { Charge }}{\text { Area }}=\frac{-Q}{4 \pi R_{1}^{2}}$
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