a cnostant freqency step down chopper system us used for thecontrol of dc series motor from 550v. The armature and field resistances are 0.03Ω and 0.02Ω respectively, the average current in the motor circuit being 300A, the choppe period beingvalue of 103 μsec. Calculate the pulse width ( Ton)if average value of counter electromotive force is 300v.