This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1920 Excerpt: ... the primary coil has 10 turns of wire and the secondary coil is made of 1,000 turns of wire, then the pressure, or voltage of the currents flowing in the secondary will be 100 times as high as the current flowing in the primary coil, but the amount of current, or amperes, will be proportionately less. As there will be ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1920 Excerpt: ... the primary coil has 10 turns of wire and the secondary coil is made of 1,000 turns of wire, then the pressure, or voltage of the currents flowing in the secondary will be 100 times as high as the current flowing in the primary coil, but the amount of current, or amperes, will be proportionately less. As there will be 150 turns of wire on the primary of your coil and your secondary will have, say, 65,000 turns of wire on it, this will step-up the pressure of the battery current of 10 volts to 4,333 volts at the terminals of the secondary coil. Now as it takes about 50,000 volts to make a spark 1 inch long, it will be seen that 4,333 volts is not nearly a high enough pressure. The condenser, however, which is shunted around the interrupter, increases the voltage, due to the inductance of the primary circuit, as it is called, to break down 1 inch of air and make a white, snappy spark. The purpose of the condenser connected across the interruptor contacts is also to take up the current from the battery when the circuit is broken at the platinum contacts which prevents arcing, and when the circuit is made again the condenser discharges through the primary coil. Experiments with a Spark Coil.--The spark of an induction coil is in itself a very remarkable and striking effect. The color, size and shape of the spark vary according to the size, shape and materials used for the electrodes. When the sparks jump between pointed wire electrodes the color and brightness are quite different than when they pass between ball and disk electrodes. If you try out the spark effects of your coil you may make a discovery. Geissler Tubes.--When an electric discharge from an induction coil is sent through a glass tube from which the air has been pumped out, the spark is broken up ...
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Seller's Description:
Very Good. Book. 8vo-over 7¾-9¾" tall. Illustrated. Decorative illustrated boards. Light shelf wear to the edges and light age toning. Rare title and early Boy Scouts reference.