Q. The magnetization curve taken at 1000 r/min on a 200-V dc series motor has the following data:
Field current, A: 5 10 15 20 25 30
Voltage, A: 80 160 202 222 236 244
The armature-circuit resistance is 0.25 and the series-field resistance is 0.25 . Calculate the speed of the motor (a) when the armature current is 25 A, and (b) when the electromagnetic torque is 36 N · m. Neglect the armature reaction.