Currents in Concentric Cables 



71 



The system is electrically equivalent to a length of con- 

 centric cable of which the two conductors are cut alternately 



Fisr. 4. 



fl- fl- 



at equidistant points in the way shown in fig. 5, repre- 

 senting a longitudinal section of the cable. If an alternating 

 current be introduced into the system of fig. 4 at any 

 link, say E, and the point A be kept at zero potential, 

 alternating currents of the same period, but of different 

 phases and amplitudes, will be found at every point of both 

 conductors. 



Fiar. 5. 



Central \^ 



Concentric) y 

 ecnj£tiC&cr\ 



Suppose the currents at the points A, B, C, D, . . Gr to be 



A cos (cot + a), Bcos (cot + b), . . Gr (cos cot+g), 



so that the values of Grg being known, and the point A being 

 kept at zero potential, the values of Ace, Bb, Q>c, . . F/ are to 

 be determined, and especially the values of Aa. 



