. Electrical world. FIG. 5. fact, attained as rapidly as that figure indicates, which is a simplediagram having no pretensions to mathematical exactitude. This figure shows that little by little the loops in spreading outend by joining on the axis of figure and finally become perfectlyspherical. From that moment the propagation will be purely trans-versal and with the velocity of light. Before attaining the limitingdistance beyond which the waves are spherical, the field followslaws much more complex; the speed is not that of light, the linesof force oscillate as Hertz has shown, and the pheno
. Electrical world. FIG. 5. fact, attained as rapidly as that figure indicates, which is a simplediagram having no pretensions to mathematical exactitude. This figure shows that little by little the loops in spreading outend by joining on the axis of figure and finally become perfectlyspherical. From that moment the propagation will be purely trans-versal and with the velocity of light. Before attaining the limitingdistance beyond which the waves are spherical, the field followslaws much more complex; the speed is not that of light, the linesof force oscillate as Hertz has shown, and the phenomena are com-plicated and difficult to analyze; for ordinary purposes, however,. the schematical representation given will suffice, satisfying ourselvesthat an investigation of what takes place at great distance. To this end it is necessary to make first a simple hypothesis onthe oscillations of which the antennae is itself the seat. The mostsimple is to assume that they are simply sinusoidal in function oftime, like the oscillations in a music pipe open at the top and excitedat the base. It results, in fact, from the experiments of Slaby andothers that the antennae when subject to normal permanent oscilla-tions has always a node of potential and a crest of current at thebase, and a crest of potential and a node of current at the summit(Fig. 7). If we neglect, lacking other recourse, the perturbations atthe extremity where the wave reflections are produced (and experi-ments seem to give this right, for in charging the form at the ex-tremity and adding there small spheres or plaques or various kinds ELECTRICAL WORLD and ENGINEER. Vol. XLIII, No. i. of points, no ch
Size: 2361px × 1059px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectelectri, bookyear1883
