A 250 V dc shunt machine has armature circuit resistance of 0.6 &ohm;. and field circuit resistance of 125 &ohm;. The machine is connected to 250 V supply mains. The motor is operated as a generator and then as a motor separately. The line current of the machine in both the cases is 50 A. The ratio of the speed as a generator to the speed as a motor is ___.

A 250 V dc shunt machine has armature circuit resistance of 0.6 &ohm;.

1.	A 250 V dc shunt machine has armature circuit resistance of 0.6 Ω. and field circuit resistance of 125 Ω. The machine is connected to 250 V supply mains. The motor is operated as a generator and then as a motor separately. The line current of the machine in both the cases is 50 A. The ratio of the speed as a generator to the speed as a motor is ___.
A.	1.22 to 1.32
B.	1
C.	2
D.	1.44
Answer» B. 1

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