Gauss's Law is one of the four Maxwell's equations. It states that the total electric flux (${\Phi }_E$) through any closed Gaussian surface is equal to the net electric charge ($q_{enc}$) enclosed by that surface divided by the permittivity of free space (${ϵ}_0$): ${\Phi }_E=\oint \vec{E}\cdot d\vec{A}=\frac{q_{enc}}{{ϵ}_0}$

• Charges outside the surface do not contribute to the net flux.