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BELL SYSTEM TECHNICAL JOURNAL 



constant over the low flux density range for all frequencies. From the 

 slope of these straight lines the hysteresis coefficient a of eq. (1) is 

 calculated to be 2.6 X 10~^ which agrees with the value 2.53 X 10~^ 



34 



32 



28 



22 



£ CO 



4 5 6 7 8 9 10 



FLUX DENSITY IN GAUSS (Bm) 



Fig. 4 — Comparison of ballistic galvanometer and a.-c. determinations of hysteresis 

 loss. Note absence of residual loss from ballistic observations. 



computed from the ballistic tests. The divergence of the data from 

 linearity at higher currents is shown by the dotted curves, which indi- 

 cate divergence of the hysteresis loop from the Rayleigh form at higher 

 flux densities. 



