Lessons in practical electricity; principles, experiments, and arithmetical problems, an elementary text-book . he cut has been made, and the space is permeated with lines offorce. The lines of force through the ironcircuit are not nearly so dense as before, sincethe resistance of the circuit has been in-creased, and with the same magnetising forcethe magnetic lines diminish as the resistanceof the circuit increases, just as in an electriccircuit the current decreases when with a con-stant pressure the resistance is increased. Ifthe removed section of the ring is now re-placed and the ring aga
Lessons in practical electricity; principles, experiments, and arithmetical problems, an elementary text-book . he cut has been made, and the space is permeated with lines offorce. The lines of force through the ironcircuit are not nearly so dense as before, sincethe resistance of the circuit has been in-creased, and with the same magnetising forcethe magnetic lines diminish as the resistanceof the circuit increases, just as in an electriccircuit the current decreases when with a con-stant pressure the resistance is increased. Ifthe removed section of the ring is now re-placed and the ring again plunged into iron filings while thecore is magnetised, a great many filings will be attracted atthe two joints, thus illustrating magnetic leakage. The densityin the ring is not now so great as when it was solid, since thejoints offer opposition to the magnetic lines, as is shown bysome lines being forced through the air across the joint. Aring with two poles is shown in C, Fig. 178, the winding being in thesame direc-tion through-out the ring,and the endsof the wirebeing ispassed. m A B Fig. 178.—The Magnetic Polarity of an Iron Ring from any point and flows around each half of the ring in anopposite direction to a diametrically opposite point and thenback to the battery. The arrows indicate the direction of cur-rent and magnetic lines of force, from which it will be seenthat a consequent N-pole is produced at the top of the ring anda S-pole at the bottom. The lines of force complete their paththrough the air from pole to pole, as will be noted by plungingthe ring into iron filings. ELECTR OMA GNETS. 189
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Keywords: ., bookcentury1900, bookdecade1900, bookpublishernewyo, bookyear1901
