ABSTRACT
This chapter explores a simple model of a metal in which the current is linearly related to the electric field. The model is to be considered as suggestive only but it does lead to a qualitative understanding of the important phenomena of conduction. Of course, an accurate description requires quantum mechanics. The Boltzmann factor describes the situation of a static electric field. But suppose the electric field is vibrating, or rotating, with a definite frequency. Owing to the large inertia of the molecules, it takes a significant time for the dipole moment to readjust or relax into the configuration demanded by the new direction of the electric field.
