Domains of Validity of Quasistatic and Quasistationary Field Approximations

The electro-quasistatic and the magneto-quasistationary approximations to Maxwell's equations are widely used to model slowly time-varying electromagnetic fields. An analysis based on characteristic times is presented which allows to decide if any of these approximations is valid for a given field problem. The domains of validity of both approximations are derived and visualized in a combined diagram.