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BELL SYSTEM TECHNICAL JOURNAL 



In other respects, however, there are marked differences: K is an 

 impedance, while w is a pure number, being the ratio of K to vR/uiC; 

 E, though approximately proportional to the frequency, is not a pure 

 number (for it is not dimensionless), while r is a pure number, being 

 the ratio of the general frequency to any fixed frequency; of the para- 

 meters, k 2 is very different from Fi, and bi is very different from g 2 . 

 The fact that (27) and (28) are of the same functional forms as (19) 

 and (20) respectively renders formally applicable the material per- 

 taining to equations (19) and (20) given in Appendix A. 



As already remarked, the effect of leakance in cables is usually 

 extremely small except at very low frequencies. Hence in the graphi- 



mpedanceK/IKJof 

 Leaky Cables 



u 



Fi=2 



cal representation of formulas (27) and (28) it will suffice for most 

 purposes to confine ourselves to the limiting case of no leakance 

 (G = 0, and hence b = and bi — 0), when these two equations reduce 

 to the same form, namely, 



= VFi-i/r. 



(29) 



This has the same functional form as (21), with w corresponding to 

 K, r to E, and F\ to k 2 ; a circumstance rendering formally applicable 

 the material pertaining to equation (21) given in Appendix A. The 

 curves in Fig. 4 represent the two components u and v of w as functions 

 of r with F\ as parameter. 



