A 15kW, 230 V dc shunt motor has armature ci r cuit r esi st ance of 0.4 &ohm; and field cir cuit resistance of 230 &ohm;. At no load and rated voltage, the motor runs at 1400 rpm and the line current drawn by the motor is 5 A. At full load, the motor draws a line current of 70A. Neglect armature reaction. The full load speed of the motor in rpm is ________.

A 15kW, 230 V dc shunt motor has armature ci r cuit r esi st ance of 0

1.	A 15kW, 230 V dc shunt motor has armature ci r cuit r esi st ance of 0.4 Ω and field cir cuit resistance of 230 Ω. At no load and rated voltage, the motor runs at 1400 rpm and the line current drawn by the motor is 5 A. At full load, the motor draws a line current of 70A. Neglect armature reaction. The full load speed of the motor in rpm is ________.
A.	540
B.	120
C.	1240
D.	140
Answer» D. 140

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