Gauss's law for electric flux through a closed surface enclosing total charge $q$ is:
A$\oint \vec{E}\cdot d\vec{s} = \varepsilon_0 / q$
B$\oint \vec{E}\cdot d\vec{s} = q / \varepsilon_0$
C$\oint \vec{E}\cdot d\vec{s} = q / (4\pi\varepsilon_0)$
D$\oint \vec{E}\cdot d\vec{s} = q\varepsilon_0$
Answer & Solution
Correct answer: B. $\oint \vec{E}\cdot d\vec{s} = q / \varepsilon_0$
Gauss's law: total electric flux through any closed (Gaussian) surface equals $q/\varepsilon_0$, where $q$ is the net charge enclosed.
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