A Gaussian surface contains zero net enclosed charge. Which statement is correct for a point located inside this surface?

The electric field there must be zero.
The electric potential there must be zero.
Both the electric field and the potential there must be zero.
None of the above.

Correct answer: None of the above.

Solution

Zero enclosed charge means the net electric flux through the surface is zero (Gauss's law), but the field at interior points need not be zero because external charges still produce fields there. Potential also need not be zero. Hence none of the definitive statements hold.

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