A charge Q is uniformly distributed on a thin spherical shell. What is the field at the centre of the shell? If a point charge is brought close to the shell, will the field at the centre change? Do your answer depend on whether the shell is conducting or nonconducting?

If we consider a thin spherical shell, then all its charge is concentrated in the centre. According to Gauss’ law, the flux through a closed surface is time the charge enclosed.


flux through the closed surface, ,


where


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