An 8 kW, 230 V, 1200 rpm dc shunt motor has armature resistance as 0.7Ω. The field current is adjusted until on no load with a supply voltage of 250 V, the motor runs at 1250 rpm and draws armature current of 1.6 A. A load torque is then applied to the motor shaft, which causes the armature current to rise to 40 A and the speed fall to 1150 rpm. The reduction in flux per pole due to the armature reaction is____%3.06

An 8 kW, 230 V, 1200 rpm dc shunt motor has armature resistance as 0.7

1.	An 8 kW, 230 V, 1200 rpm dc shunt motor has armature resistance as 0.7Ω. The field current is adjusted until on no load with a supply voltage of 250 V, the motor runs at 1250 rpm and draws armature current of 1.6 A. A load torque is then applied to the motor shaft, which causes the armature current to rise to 40 A and the speed fall to 1150 rpm. The reduction in flux per pole due to the armature reaction is____%3.06
Answer» An 8 kW, 230 V, 1200 rpm dc shunt motor has armature resistance as $0.7 Ω$ . The field current is adjusted until on no load with a supply voltage of 250 V, the motor runs at 1250 rpm and draws armature current of 1.6 A. A load torque is then applied to the motor shaft, which causes the armature current to rise to 40 A and the speed fall to 1150 rpm. The reduction in flux per pole due to the armature reaction is____% 3.06

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