Elementary treatise on electricity and magnetism : (1905)
Foster, G. C. (George Carey), 1835-1919, Joubert, J. (Jules François), 1834-1910, Porter, Alfred W. (Alfred William), 1863-1939 · London ; New York ; Bombay : Longmans, Green, and Co. · leaf 412
motion of the plate. The experiment may be easily made by means of a disc whichis made to rotate between the poles ofan electromagnet (Fig. 273). The disc,which before the passage of the cur-rent turns easily, offers a considerablelesistance as soon as the electromagnetis excited. The effect is… … Fig. 273. In like manner, if 326] FOUCAULT CURRENTS 389 the two poles, b and a, of an electromagnet by a twisted thread,the cube, if left to itself, spins round rapidly, but it stops themoment the current is turned on (Fig. 275). It is clear that a pole which can rotate about an axis concentric
Electricity · Magnetism
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