# Question: a series of excitation dc motors have an armature winding...

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A series of excitation DC motors have an armature winding resistance of 0.3 ohms, a field winding resistance of 0.1 ohms, a rotational speed of 650 rpm, a back emf is 120 V, and an armature current of 78 A. If the torque is constant, 0.6 ohms is connected in series with the armature, what is the speed of the motor after it is stabilized?