State Gauss’s law in electrostatics.

The total electric flux through any closed surface is equal to $\frac{1}{{\mathrm{ϵ}}_0}$ times the net charge enclosed by the surface. Here ${\mathrm{ϵ}}_0$ is the permittivity of free space. Mathematically the Gauss’s law or Gauss’s theorem can be stated as ${\text{∮}}_{\mathrm{s}}\mathrm{E}.\mathrm{ds}=\frac{\mathrm{q}}{{\mathrm{ϵ}}_0}$ Here q is the total charge enclosed by the surface S. $\text{∮}\text{'}$ denotes that the surface should be a closed surface enclosing a certain volume inside which the total charge is q.