# Flux Flux refers to a flow of matter or energy. Examples include water through a pipe, blood through veins, or air over an airplane's wing. While there's nothing directly *flowing* in an electric field, the term flux is used to describe the total strength of a field. In the simplest case with a uniform field of magnitude $E$ perpendicular to an area $A$, the flux is described as follows: $$ \Phi = EA$$ - $E$ refers to the amplitude - $A$ refers to the area