An unsaturated dc shunt motor drives a constant torque load at a speed at 1000 rpm taking an armature current of 20 A when 230 V is applied to the motor. If the applied voltage is reduced to 115 V, the motor runs at
A. 500 rpm taking an armature current of 20 A.
B. 1000 rpm taking an armature current of 20 A.
C. 500 rpm taking an armature current of 40 A.
D. 1000 rpm taking an armature current of 40 A.
Answer:D
An unsaturated dc shunt motor drives a constant torque load at a speed at 1000 rpm taking an armature current of 20 A when 230 V is applied to the motor. If the applied voltage is reduced to 115 V, the motor runs at
A. 500 rpm taking an armature current of 20 A. B. 1000 rpm taking an armature current of 20 A. C. 500 rpm taking an armature current of 40 A. D. 1000 rpm taking an armature current of 40 A.