The angle between the rotating stator flux and rotor poles is called _________ angle.

A. Synchronizing
B. Obtuse
C. Torque
D. Power factor

Slip-rings in a synchronous motor carry____________?

A. Direct current
B. Alternating current
C. No current
D. All of the above

A synchronous motor working at leading power factor can be used as____________?

A. Voltage booster
B. Phase advancer
C. Nosie generator
D. Mechanical synchronizer

The standard full-load power factor ratings for synchronous motors are___________?

A. Zero or 0.8 leading
B. Unity or 0.8 lagging
C. Unity or 0.8 leading
D. Unity or zero

The rotor copper losses, in a synchronous motor, are met by____________?

A. D.c. source
B. Armature input
C. Motor input
D. Supply lines

A synchronous motor will always stop when:______________?

A. Supply voltage fluctuates
B. Load in motor varies
C. Excitation winding gets disconnected
D. Supply voltage frequency changes

The speed regulation of a synchronous motor is always___________?

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

. In a synchronous motor which loss varies with load ?

A. Windage loss
B. Bearing friction loss
C. Copper loss
D. Core loss

For V-curves for a synchronous motor the graph is drawn between:_______________?

A. Armature current and power factor
B. Terminal voltage and load factor
C. Power factor and field current
D. Field current and armature current

An over-excited synchronous motor takes__________?

A. Leading current
B. Lagging current
C. Both a. and (b)
D. None of the above