WA V ECU IDE TRANSMISSION 



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Because of the property of inertia with which all lines of force are assumed 

 to be endowed, the central section of a-b, which is already greatly extended 

 due to curvature, continues in motion for some time after the two ends, at- 

 tached to the conductors, have come to rest. The result is shown approxi- 

 mately by Fig. 6.3-1 (e). An instant later and perhaps after the two ends of 

 line of force a-b have started on their return journey, the line of force c-d 

 approaches sufficiently close to a-b that a coalescence ensues [Fig. 6.3-1 (f)]. 

 An instant later lission takes place as illustrated in Fig. 6.3-1 (g), leaving a 

 portion of the energy of each a-b and c-d now shared by a radiated com- 



Fig. 6.3-1. Successive epochs in a highly idealized representation of radiation from the 

 flared end of a transmission line. 



ponent, r, and a reflected component, .r. That the two components r and x 

 should travel in opposite directions seems reasonable when it is noted that 

 lines of electric force in .v are in the same direction as in the adjacent portion 

 of r. They may therefore be expected to repel. The first of these components, 

 r, appears to the transmitter as though it were a resistance since it represents 

 lost energy. The second, .v, appears as a reactance since it represents energy 

 returned to the transmitter. The radiated component, r, will be followed by 

 other components ri, r-i, etc., as represented in Fig. 6.3-1 (h). 



In the radiated wave front, the two components E and H are everywhere 

 mutually perpendicular and in the same phase. Because the wave front 



