1 Answer

Answer :

If a D.C. motor is connected across the A.C. supply it will burn due to heat produced in the field winding by eddy currents.

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Last Answer : The current drawn by the armature of D.C. motor is directly proportional to the torque required.

Last Answer : In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to 25% of the previous value.

Last Answer : The speed of a D.C. series motor is inversely proportional to the armature current.

Last Answer : The starting resistance of a D.C. motor is generally low.

Last Answer : In case the conditions for maximum power for a D.C. motor are established, the efficiency of the motor will be less than 50%.

Last Answer : By looking at Commutator part of the motor, it can be easily confirmed that a particular motor is D.C. motor.

Last Answer : In a D.C. shunt motor, under the conditions of maximum power, the current in the armature will be more than full-load current.

Last Answer : The armature may burn if the back e.m.f. of a D.C. motor vanishes suddenly.

Last Answer : In a D.C. shunt motor, speed is independent of armature current.

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Description : Armature control of DC motor

Last Answer : Armature control of DC motor