Visual aids

Abstract

Permanent Magnets (col, 24 min) deals briefly but interestingly with the whole subject of magnetism. The development of permanent magnet materials is traced up to the present day showing, in particular, how the design of equipment, e.g. the telephone handset, has been dependent upon the magnets incorporated within it. The special techniques of manufacture are illustrated — alloy melting, magnetising and testing — and the crystal structure of the materials is explained. Of special interest to colleges and schools is the reference to the hysteresis loop — a concept difficult to explain by chalk and talk, yet clearly expounded here by animation. This section could perhaps be classed as a perfect example of using film as a real teaching aid. Have the sponsors thought of making an 8mm film loop of this part of the film? It would certainly be warmly welcomed. Free loan from the Publicity Department, English Steel Corporation, River Don Works, Sheffield 9.

Citation

(1965), "Visual aids", Education + Training, Vol. 7 No. 12, pp. 566-566. https://doi.org/10.1108/eb015658