If the total charge enclosed by a surface is zero, does it imply that the electric field everywhere on the surface is zero ? Conversely, if the electric field everywhere on a surface is zero, does it imply that net charge inside is zero.
If the total charge enclosed by a surface is zero, does it imply that the electric field everywhere on the surface is zero ? Conversely, if the electric field everywhere on a surface is zero, does it imply that net charge inside is zero.
Electric flux $\phi=\oint_{S} \vec{E} \cdot d \vec{S}=\frac{q}{\epsilon_{0}}$
In left side of equation, $\overrightarrow{\mathrm{E}}$ is electric field on the surface by charges inside and outside the surface. But, in right side of equation, $q$ is the charge enclosed by the surface.
It means, if $q=0$, then may $\mathrm{E} \neq 0$ because there may be $\mathrm{E}$ due to charges outside the surface. But, if $\mathrm{E}=0$, then $q=0$.(Charge enclosed by surface)
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