A metal spherical shell has an inner radius `R_(1)` and outer radius `R_(2)`. A charge Q is placed at the center of the spherical cavity. What will be surface charge density on (i) the inner surface, and (ii) the outer surface ?

Explanation

Here, the charge placed at the centre of the spherical cavity is positively charged. So, the charge created at the inner surface of the sphere due to induction will be -Q and due to this charge created at outer surface of the sphere is +Q.
Now, surface charge density ont he inner surface `=(-Q)/(4piR_(1)^(2))` and
Surface charge density on the inner surface `=(+Q)/(4piR_(2)^(2))`
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