If the field of a D.C. shunt motor gets opened while motor is running______________?
Correct answer: C. the motor will attain dangerously high speed 1
- A. the speed of motor will be reduced %
- B. the armature current will reduce
- C. the motor will attain dangerously high speed 1
- D. the motor will continue to nuvat constant speed
Explanation
Opening the shunt field greatly reduces flux, and motor speed varies approximately inversely with flux for a given back e.m.f. The motor can therefore accelerate to a dangerously high speed.
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