Practice question · Multiple choice
A Gaussian surface is drawn around an electric dipole. Why is the total flux through it zero even though the field on it is not?
Hints
- Flux counts only the NET enclosed charge.
- A dipole is two equal and opposite charges, so the net enclosed charge is zero, but each charge still produces a field.
Show the answer
A. Zero flux, but a substantial field everywhere on the surface
Why
The dipole encloses and , so and the total flux vanishes. The field certainly does not: inward flux on one side exactly cancels outward flux on the other. Zero total flux never implies zero field.
Practise Electrostatics in Vacuum
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