272 INDEX 



PAGE 



Distributed windings, for alternator fields 121 



r.m.f. of. See E.m.f. 



m.m.f. of D.C 165 



m.m.f . of single-phase 123 



m.m.f. of polyphase 128 



Eccentric armature, force upon 248 



Eddy currents, nature of 40 



prevention of 41 



separation of, from hysteresis 53 



Electric circuit, equivalent, torque from 260 



Electric loading, specific, definition of 163 



Electromagnet, A.C., average tractive effort of 254 



average tractive effort of D.C 252 



lifting 243 



rotary, torque of 253 



tractive, force of 248 



Electromagnetic inertia 180 



E.m.f., average reactance, as criterion for commutation 235 



formula for induced 57 



induced in A.C. machines 65 



induced in D.C. machines 75 



induced in an unsymmetrically spaced transmission line 205 



methods of inducing 55 



ratio. (See Ratio of transformation.) 



ratio in a rotary converter 78 



regulation in an alternator 156 



regulation in a rotary converter 78 



vs. inductance 185 



Energy, density of, in magnetic field 240 



lost in hysteresis cycle 38 



of magnetic field, none consumed in 177 



stored in magnetic field, description of 177 



stored in magnetic field, formulae for 181 



Equivalent electric circuit, torque from 260 



permeance, definition of . 184 



secondary winding, reduced to primary 133 



Exciting current in an induction motor 130 



in a transformer vs. magnetizing current 80 



of a transformer, exciting volt-ampems 82 



of a transformer, saturated core 84 



unsaturated core 81 



of machinery. See Saturation curves. 



Factor, air-gap, definition of 90 



in induction motor 98 



amplitude 84 



