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BELL SYSTEM TECHNICAL JOURNAL 



The value of 7 is finite for all values of co/ except 7r/2 and S{t/2) 

 where it becomes infinite. Near these values, therefore, the equation 

 fails for the reason that the higher powers of w were neglected in the 

 expression for the condenser conductance (Eq. 4). 



trOjt 



Fig. 7 — The value of /3 during one cycle. 



Let the heavy line abob'a', Fig. 9, be the trace of the ideal curve 



X = cos Oj/, 



3' = -E(-i) 



T 1 



cos m coi 



m 



(13) 



The curve followed by the value of Cs in equation (12) is then of the 

 form shown by the light line ac'a'ca, which again is traced in the 



-i.a- 



-1.5 



Fig. 8 — The vahie of 7 during one cycle. 



clockwise direction. When the apparatus is used for an actual 

 material having positive hysteresis, the loop is made narrower at the 

 II axis by this distortion, but the amount of the decrease in width 



