418 



TABLE 426.— THE CALCULATION OF THE HIGH-FREQUENCY RESISTANCE 

 OF CONDUCTORS (continued) 



Part 1. — Resistance ratio "F" for isolated round wires 



Resistance ratio F of isolated round wire, as a function of the square root of the fre- 

 quency divided by the direct current resistance per 1000 ft of conductor. 



10 20 30 40 50 60 70 80 90 100 



1.000 1.000 1.0005 1.0025 1.008 1.019 1.038 1.069 1.114 1.173 1.247 



100 120 140 160 180 200 250 300 350 400 500 



1.247 1.427 1.631 1.836 2.036 2.231 2.715 3.201 3.688 4.176 5.152 



Part 2. — Values of resistance ratio for isolated tubular conductors 



t, thickness of wall of tube ; d, outer diameter of tube 



SMITHSONIAN PHYSICAL TABLES 



