Lessons in practical electricity; principles, experiments, and arithmetical problems; over four hundred illustrations; an elementary text book (1909)
Swoope, C. Walton (Coates Walton), d. 1901 · New York, D. Van Nostrand company · leaf 184
v>*U\** v.; . Vy- ■ - - … Fig. 150.—Clock Rules for Polarity. Fig. 151.—Magnetic Field of aSolenoid. Made by iron filings upon a horizontalpiece of cardboard. Exp. 55 : Wind a helix about 1 inch in diameter and 4 inches long.Cut a tongue in a sheet of cardboard equal to the inside diameter ofthe helix, and pass it…
Electricity · Magnetism
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
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