. Electrical world. FIG. 4.—RESULTANT OF PHASE DIFFERENCE. that the ordinates and abscissa; will correspond to those of the cor-responding points of the hysteresis curve for the sample, and thefluorescent screen will show a hysteresis curve which will have thesame appearance as the usual curve plotted from arrangement of circuits which is here adopted allows of throw-ing the current on the three coils in series, or on the top or side coilsalone, so as to check up the action of either set upon thespot. Each of the coils should be placed with its axis perpen-dicular to that of t
. Electrical world. FIG. 4.—RESULTANT OF PHASE DIFFERENCE. that the ordinates and abscissa; will correspond to those of the cor-responding points of the hysteresis curve for the sample, and thefluorescent screen will show a hysteresis curve which will have thesame appearance as the usual curve plotted from arrangement of circuits which is here adopted allows of throw-ing the current on the three coils in series, or on the top or side coilsalone, so as to check up the action of either set upon thespot. Each of the coils should be placed with its axis perpen-dicular to that of the tube, so that the axes will cross in frontof the central diaphragm. The size of the wire used in the should be focused beforehand upon some well-defined object, suchas a lighted candle. In Figs. 2 and 3 are shown photographic reproductions of hys-teresis curves which were obtained in this way. The first curve is. FIG. 5.—ME.\SUREMENT OF PHASE DIFFERENCES IN ALTERNATINGCIRCUITS. that of a hard file-steel, while the second is the curve of an iron ofbad quality. The photographs were taken without enlargement on aplate of average sensitiveness. The tube was supplied from a staticmachine having two discs of about 60 cm. diameter. The plate wasgiven an exposure of about I minute in order to obtain the curveitself. To obtain the lines corresponding to the axes, about 10 sec-onds is necessary. It should be noted that in tracing the hysteresiscurve the axis of abscissas should not be drawn directly from thecurve, but the abscissae are to be diminished in each case by the valueof the so-called demagnetizing force. As the apparatus does notgive this correction automatically, it should be introduced whendrawing the curve from the above data. The use of the Braun tube with the present arrangement gives aneasy method of determining the angle of lag between current andelectromotive force in an alternating-
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectelectri, bookyear1883
