A historical analysis of electric currents in textbooks: A century of influence on physics education

The typical model of electric current which we present to students is one of electron movement between points at different potentials. The problems associated with this model of electricity have been the subject of much educational research, particularly with respect to the use of analogies. The water-circuit analogy, especially, has received considerable attention. Despite this, students continue to hold remarkably persistent alternative conceptions about the nature of simple circuits. Historically, the electromagnetic field theories of Faraday and Maxwell constitute important steps towards modern understanding of transmission of electric current along a wire. Textbooks from 1891 to 1991, however, reflect remarkably little change in their presentation of direct-current circuitry, most texts by implication portraying, in various ways, a fluid model which predates Faraday. Against this background, this paper describes the ways in which textbooks interpret historical developments for teaching texts and the time which may elapse before such developments have an impact in the classroom. It also highlights important issues relating to the intrinsic merit of contemporary textbook treatments of electricity and examines their importance with respect to classroom teaching.