Practice question · Multiple choice
A balloon is charged and its charge stays fixed. If you double the radius of an imaginary sphere drawn around it, what happens to the total electric flux through the sphere?
Hints
- Gauss’s law: . Does appear anywhere?
- The field weakens as but the area grows as , watch them cancel.
Show the answer
B. Nothing, flux depends only on the enclosed charge
Why
Flux counts field lines crossing the surface, and every line from the charge crosses any enclosing sphere exactly once. The field and area cancel perfectly, that cancellation is Gauss’s law.
Practise Electric Field and Gauss's Law
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