Question

The electric flux through a closed surface area $S$ enclosing charge $Q$ is $\phi$ . If the surface area is doubled, then the flux is

• A. $2\,\phi$
• B. $\phi /2$
• C. $\phi /4$
• D. $\phi$

Answer 1

Answer: (A)

$2\,\phi$

Answer 2

By Gauss' theorem $\phi_{E}=\int \vec{E} \cdot d \vec{S}=\frac{q}{\varepsilon_{0}} \phi_{E} \propto \int d S$ $\therefore$ Flux will also doubled, ie, $2 \phi$