FERROMAGNETISM — IS IT A FREE LUNCH?

A Lecture by Prof. Philip Beckley of the Wolfson Centre, University of Wales at Cardiff on 3 February 1998

Magnetism occurs naturally and appears to offer something for nothing, but the speaker posed the title question through outlining and then investigating the energy transformations which occur when magnetic effects arise from electrical activities.
With the aid of several benches full of apparatus and also visual illustrations he traced the development and increasing sophistication of the measures taken to reduce losses occurring during these transformations. Central to these are the minimalisations achieved through the lamination of iron cores in transformers and through other means of reducing hysteresis losses — magnetic eddies, in effect, within the core.
Samples of laminations were circulated and large-scale applications in Welsh industrial sites were illustrated .
The various illustrations of principles extended from simple wire suspensions over floating objects, as first demonstrated by Faraday at the Royal Institution, to elaborate electromagnetic commercial devices in use today.
The demonstrations culminated in an impressive tour-de-force, when the speaker donned heavy steel-shod boots and climbed into a sturdy wooden frame on which a small electromagnet was mounted. The audience held its breath when the amply-proportioned lecturer lay on his back, put both feet firmly on the plate of the electromagnet and switched on. To much relief and sustained applause, Professor Beckley hung suspended upside-down with no support save his demonstrated principle — a most effective demonstration.
The speaker concluded with an admission that there are no free lunches, although ingenuities of science and technologies can at least reduce costs to marginal proportions.

Geoff Catchpole