Synchronous motors

maintaining constant excitation

running the motor on leading power factors

providing damper bars in the rotor pole faces

oscillations cannot be damped

armature current and field current

power factor and speed

field current and speed

field current and power factor

the armature current is maximum

the armature current is minimum

the armature current is zero

none of the above

locked-rotor torque

synchronous torque

pull up torque

reluctance torque

more than the supply voltage

less than the supply voltage

equal to the supply voltage

none of the above

high excitation only

low excitation only

both (A) and (B)

none of the above

lower stability limit

high stability limit

good speed regulation

good voltage regulation

slip torque

pull-out torque

breaking torque

synchronising torque

3000 r.p.m.

1500 r.p.m.

750 r.p.m.

none of the above