If a D.C. shunt motor is working at no load and if shunt field circuit suddenly opens

A Nothing will happen to the motor
B This will make armature to take heavy current, possibly burning it
C This will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses
D Motor will run at very slow speed

Correct Answer: This will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses

Bissoy MCQ
#Electrical Engineering #D.C. Motors

Related Questions

If a D.C. shunt motor is working at full load and if shunt field circuit suddenly opens
A This will make armature to take heavy current, possibly burning it
B This will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses
C Nothing will happen to motor
D Motor will come to stop
In a differentially compounded D.C. motor, if shunt field suddenly opens
A The motor will first stop and then run in opposite direction as series motor
B The motor will work as series motor and run at slow speed in the same direction
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D The motor will not work and come to stop
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B 6
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E all of the above methods

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