Computer Programming MCQs

5739 MCQs  (Page 91 of 574)

For power factor correction, synchronous motors operate at____________?
A. No-load and greatly over-excited fields
B. No-load and under-excited fields
C. Normal load with minimum excitation
D. Normal load with zero excitation
The construction of a synchronous motor resembles____________?
A. A series motor
B. An induction motor
C. An alternator
D. A rotary converter
A synchronous machine with low value of short-circuit ratio has___________?
A. Lower stability limit
B. High stability limit
C. Good speed regulation
D. Good voltage regulation
The coupling angle or load angle of synchronous motor is defined as the angle between the__________?
A. Rotor and stator teeth
B. Rotor and the stator poles of opposite polarity
C. Rotor and the stator poles of the same polarity
D. None of the above
If the synchronous motor, properly synchronised to the supply is running on no load and is having negligible loss then_____________?
A. The stator current will be zero
B. The stator current will be very small
C. The stator current will be very high
D. The back e.m.f. will be more than the supply voltage
In a synchronous motor, the breakdown torque is__________?
A. Directly proportional to the square of the applied voltage
B. Directly proportional to applied voltage
C. Inversely proportional to applied voltage
D. None of the above