In a DC motor the inter-pole winding is connected in________________?
A. series with field winding
B. series speed armature winding
C. parallel big field winding
D. parallel with armature winding
The total losses in a well designed D.C. generator of 10 kW will be nearly______________?
A. 100 W
B. 500 W
C. 1000 W
D. 1500 W
In D.C. machines the residual magnetism is of the order of_________________?
A. 2 to 3 per cent
B. 10 to 15 per cent
C. 20 to 25 per cent
D. 50 to 75 per cent
The starting resistance of a D.C. motor is generally_______________?
A. low
B. around 500 Q
C. 1000 Q
D. infinitely large
Which of the following motors is usually used in house-hold refrigerators ?
A. D.C. shunt motor
B. D.C. series motor
C. Single phase induction motor (split phase start or induction run motor)
D. Reluctance motor
E. Synchronous motor
The main disadvantage of the Ward-Leonard control method is______________?
A. high initial cost
B. high maintenance cost
C. low efficiency at Hght loads
D. all of the above
No-load speed of which of the following motor will be highest ?
A. Shunt motor
B. Series motor
C. Cumulative compound motor
D. Differentiate compound motor