Synchronous motors are_____________?

A. Not-self starting
B. Self-starting
C. Essentially self-starting
D. None of the above

Synchronsizing power of a synchronous machine is_____________?

A. Direcly proportional to the synchronous reactance
B. Inversely proportional to the synchronous reactance
A. Equal to the synchronous reactance
D. None of the above

When the stator windings are connected in such a fashion that the number of poles are made half, the speed of the rotor of a synchronous motor___________?

A. Remains same as the original value
B. Decreases to half the original value
C. Tends to becomes zero
D. Increases to two times the original value

When load on an over-excited or under excited synchronous*motor is increased, rate of change of its armature current as compared with that of power factor is___________?

A. More
B. Less
C. Equal
D. Twice

Riunting in a synchronous motor takes place___________?

A. When supply voltage fluctuates
B. When load varies
C. When power factor is unity
D. Motor is under loaded

The percentage slip in case of a synchronous motor is____________?

A. 1%
B. 100%
C. 0.5%
D. Zero

When the field of a synchronous motor is under-excited, the power factor will be____________?

A. Leading
B. Lagging
C. Unity
D. Zero

The oscillations in a synchronous motor can be damped out by_______________?

A. Maintaining constant excitation
B. Running the motor on leading power factors
C. Providing damper bars in the rotor pole faces
D. Oscillations cannot be damped

A synchronous motor can operate at____________?

A. Lagging power factor only
B. Leading power factor only
C. Unity power factor only
D. Lagging, leading and unity power factors

If load (or torque) angle of a 4-pole synchronous motor is 6° electrical, its value in mechanical degrees is__________?

A. 2
B. 3
C. 4
D. 6