A dc series motor is coupled to a load whose torque is proportional to speed. It

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Question
A dc series motor is coupled to a load whose torque is proportional to speed. It is fed by a single phase ac supply through a full converter. When speed is 500 rpm, firing angle is 45�. It is desired to raise the speed. It will be necessary to
Options
A. decrease the firing angle
B. increase the firing angle
C. either decrease or increase the firing angle depending on the required speed
D. decrease the load torque

Correct Answer

decrease the firing angle

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