A. spark excessively
B. have poor efficiency
C. have poor power factor
D. all of the above
Related Mcqs:
- A.C. series motor as compared to D.C. series motor has__________?
A. smaller brush width
B. less number of field turns
C. more number of armature turns
D. less air gap
E. all of the above - If starting winding of a single-phase induction motor is left in the circuit, it will____________?
A. run faster
B. spark at light loads
C. draw excessive current and overheat
D. run slower - When a D.C. series motor is connected to A.C. supply, the power factor will be low because of____________?
A. high inductance of field and armature circuits
B. induced current in rotor due to variations of flux
C. fine copper wire winding
D. none of the above - In A.C. series motor compensating winding is employed to_____________?
A. reduce the effects of armature reaction
B. increase the torque
C. reduce sparking at the brushes
D. none of the above - In a A.C. series motor armature coils are usually connected to commutator____________?
A. through resistance
B. through reactances
C. through capacitors
D. solidly - A capacitor-start single phase induction motor is switched on to supply with its capacitor replaced by an inductor of equivalent reactance value. It will______________?
A. start and then stop
B. start and run slowly
C. start and run at rated speed
D. not start at all - After the starting winding of a single phase induction motor is disconnected from supply, it continues to run only on ______________?
A. running winding
B. rotor winding
C. field winding
D. compensating winding - In case of a shaded pole motor the direction of rotation of the motor is__________?
A. from main pole to shaded pole
B. from shaded pole to main pole
C. either of the above depending on voltage
D. either of the above depending on power factor - Two-value capacitor motor finds increased application as compressor motor in small home air-conditioners because_____________?
A. it is comparatively cheaper
B. it has almost non-destructible capacitor
C. it has low starting as well as running currents at relatively high power factor
D. it is quiet in operation - In case of a reluctance motor, when the load is increased so that it cannot maintain synchronous speed the motor will_____________?
A. become unstable
B. draw excessive armature current and may burn out
C. fall out of synchronism and come to stand still
D. run as induction motor
