A dc shunt motor operating at an armature terminal voltage of 125 V is observed to be operating at a speed of 1180 r/min. When the motor is operated unloaded at the same armature terminal voltage but with an additional resistance of 5Ω in series with the shunt field, the motor speed is observed to be 1250 r/min. i. Calculate the resistance of the series field. ii. Calculate the motor speed which will result if the series resistance is increased from 5Ω to 15Ω.

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DC Generator

An electromechanical machine which converts input mechanical energy to respective output electric energy is called a generator.