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Question
Find the electric field intensity due to a uniformly charged spherical shell at a point (ii) inside the shell. Plot the graph of electric field with distance from the centre of the shell.
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Solution
Field inside the shell: The point P will be inside the shell. The Gaussian surface is again a sphere through P centred at O.
The flux through the Gaussian surface, calculated as before, is E × 4πr2.
However, in this case, the Gaussian surface encloses no charge. Gauss’s law then gives
E = 4πr2 = 0
∴ E = 0
Thus, the field due to a uniformly charged thin shell is zero at all points inside the shell
Graph showing the electric field with the distance from the centre of the shell:
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