In case of D.C. shunt motors the speed is dependent on back e.m.f. only because
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
Answer: Option D
Solution(By Examveda Team)
In the case of D.C. shunt motors, the speed is dependent on back e.m.f. only becauseFlux is practically constant in D.C. shunt motors.In a shunt motor, the field winding is connected in parallel with the armature winding. This configuration ensures that the flux (magnetic field) remains relatively constant, regardless of changes in load or speed.
As a result, the back electromotive force (e.m.f.) generated in the armature is primarily determined by the speed of the motor and not significantly affected by changes in the flux.
Therefore, the correct option is Flux is practically constant in D.C. shunt motors.
This Question Belongs to Electrical Engineering >> D.C. Motors
For dc Motor,
Eb proportional to flux and speed
In dc shunt motor, the flux is practically almost constant. Hence the speed of the motor is only depend on e.m.f.