A 220 V, 20 A, 1000 rpm, separately excited dc motor has an armature resistance of 2.5&ohm;. The motor is controlled by a step down chopper with a frequency of 1 kHz. The input dc voltage to the chopper is 250 V. The duty cycle of the chopper for the motor to operate at a speed of 600 rpm delivering the rated torque will be

A 220 V, 20 A, 1000 rpm, separately excited dc motor has an armature r

1.	A 220 V, 20 A, 1000 rpm, separately excited dc motor has an armature resistance of 2.5&ohm;. The motor is controlled by a step down chopper with a frequency of 1 kHz. The input dc voltage to the chopper is 250 V. The duty cycle of the chopper for the motor to operate at a speed of 600 rpm delivering the rated torque will be
A.	0.518
B.	0.608
C.	0.852
D.	0.902
Answer» C. 0.852

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