Synchronous Motors

A. no change of power factor
B. lagging power factor with over-excitation
C. leading power factor with under-excitation
D. leading power factor with over-excitation

A. 45°
B. 60°
C. 90°
D. 120°

A. has large values for low excitation i niy
B. has large values for high excitation only
C. has large values for low and high excitation
D. any of the above

A. d.c. series machines
B. d.c. shunt machines
C. d.c. compound machines
D. any of the above

A. one hour
B. one minute
C. one second
D. none of the above

A. slip torque
B. pull-out torque
C. breaking torque
D. synchronising torque

A. D.C. series motor
B. synchronous motor
C. Squirrel cage induction motor
D. Wound round induction motor

A. varies with power factor
B. varies with speed
C. varies with the load
D. remains constant at all loads

A. zero
B. one
C. two
D. infinity

A. more than the supply voltage
B. less than the supply voltage
C. equal to the supply voltage
D. None of these