Electricity and magnetism for advanced students (1920)
Starling, Sydney George, 1873- · London Longmans, Green · leaf 99
he heat produced by the passage of thecurrent has also been employed in the construction of ammeters andvoltmeters. The current passes through a fine wire which is therebyheated. The expansion is observed by some mechanical multiplyingarrangement. The Cardew voltmeter is an example of this form… … Fig. 83. currents. The hot wire instruments, however, are very liable to changeof zero, and the fact that the heating is proportional to the square ofthe current renders the scale uneven, and further, the multiplyingmechanism is a frequent source of uncertainty. Soft Iron Instruments.—Soft Iron…
Electricity · Magnetism
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