ELECTRIC OSCILLATIONS AND ELECTRIC WAVES. 217 



and I t = + f/. This is, of course, a very special problem 

 because both branches are exactly like the main line, and in 

 this case one ninth of the energy of the original wave is reflected 

 back on the main line and four ninths of the energy of the original 

 wave enters each branch. 



119. Transmission line surges which follow the switching on 

 of a generator. When a generator of negligible resistance and 



open end of line 



+E 



+E 



c 



-E 



-E +1 



+E +1 



axis of I 



axis of time 



curve of '_ current at B 



Fig. 153. 



The upper part of the figure shows a ribbon wave which shoots out from a 

 suddenly connected generator and is repeatedly reflected at both ends of the line. 

 The lower part of the figure shows the value of the current at B as a function of 

 elapsed time. 



inductance is suddenly switched on to a line, a ribbon wave of 

 generator voltage and corresponding current shoots out over the 

 line. Assuming line resistance to be negligible and line insulation 

 to be perfect, this ribbon wave is reflected back and forth as 

 represented in Figs. 153, 154 and 155, and by adding voltages 



