CAPACITY OF SINGLE-PHASE LINE 87 



also at the same potential. The potential of the cylinder 

 will be 



r 2 DB 



In the same way, let the wire B be replaced by a solid 

 cylinder of radius p and center E, as in Fig. 22. 



... t .. 



Fig. 22. 



The potential of this cylinder, which carries q units 

 per centimeter, will be 



AE DB 



p p 



since the second cylinder is symmetrical with the first. 

 Thus the potential difference between the two cylinders is 



DB _ q 

 p C 

 where C is the capacity per centimeter of line. 



ThuS C =~ *B- -" 



4log 



p 



XT D ij i* jj 



Now = , 



P FA 



since F is a point on the circle. 



DB DB - p 



rr U f 

 Therefore 



p DB + p - s 



where s is the interaxial distance between the two solid 

 cylinders, and is equal to DE, Fig. 22. 



