The key to the Maxwell mystery

Any claim that the study of the development and consequences of Maxwell's equations in classical electromagnetic theory is simple must be taken with a pinch of salt. It is as difficult as most other topics in the advanced stages of a physics course. In Classical Electromagnetism , Robert H. Good has made a commendable attempt to produce a text that is more didactic than most of its rivals. It is aimed at students "familiar with vectors and with calculus... they don't need to know much about electromagnetism", in the second and/or later years of a course in physics. It would fit well into the same stage of a British programme.

Starting from the laws of Coulomb, Gauss, Faraday and Amp re, and including displacement current in an empirical way, Good produces Maxwell's equations only a quarter of the way through the text. He then uses the equations to derive results that in other books are usually obtained before the equations are made explicit. He progresses consistently to finish with chapters on radiation, on its interaction with matter, on antennas, on waveguides and on relativity and electromagnetism. Throughout the text Good provides many worked examples, some of which provide a feel for orders of magnitude while some are used to illustrate the physical meaning of equations that have been derived. These examples, and the 20 or so other problems at the end of each chapter (half of which have answers given, sometimes with cryptic solutions), should be of great help to students and could aid lecturers in communicating the physical meaning of formulas.

At the very beginning of the book, Good provides a rather indigestible chapter on vectors, in spite of his claim that "we develop the requisite formalism... as we need it". At its end he includes a floppy disk with five programs and a brief appendix on programming visualisations of electromagnetic fields, neither of which seems to add much to the text.

These are minor criticisms of a work which should adorn the bookshelves of all those who present modules on classical electromagnetism. Though its price might discourage adoption, it should be recommended at least as supplementary reading for students following the subject. They could well find its approach more sympathetic than other current texts. The many demonstrations of the use of theory in problem solving certainly should help their understanding of a demanding subject.

D. E. G. Williams was senior lecturer in physics, University of Loughborough.