electromagnetism (elektromagnetizm)

The collective term for the phenomena which rest upon the relation between electric currents and magnetism. It comprises the effects of an electric current in directing a magnetic needle and in inducing magnetism in a magnetic substance, as soft iron, and also the analogous effects of a magnet in directing a movable conductor traversed by a current, or in inducing in a conductor an electric current. The directive power of an electric current upon a magnet was discovered by Oersted; it is the principle involved in all forms of galvanometer (which see). The power of an electric current to induce magnetism, and of a magnet to induce an electric current, is treated under induction; these latter phenom. ena form the basis of the electromagnet and of all forms of magneto-electric and dynamo-electric machines. electromagnet ist (ē-lek-trō-mag'net-ist), n. One skilled in electromagnetism.