In case of D.C. shunt motors the speed is dependent on back e.m.f. only because____________?
Correct answer: D. flux is practically constant in D:C. shunt motors
- A. back e.m.f. is equal to armature drop
- B. armature drop is negligible
- C. flux is proportional to armature current
- D. flux is practically constant in D:C. shunt motors
Explanation
Motor speed is approximately proportional to back e.m.f. divided by flux, and the shunt field maintains nearly constant flux. Consequently, speed is primarily determined by the back e.m.f.
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