## DC Motors Quiz Question with Answer

11. The ratio of starting torque to full-load torque is least in case of

1. series motors
2. shunt motors
3. compound motors
4. none of the above

12. The speed of a D.C. motor can be varied by varying

1. field current
2. applied voltage
3. resistance in series with armature
4. any of the above

13. The speed of a D.C. series motor is

1. proportional to the armature current
2. proportional to the square of the armature current
3. proportional to field current
4. inversely proportional to the armature current

14. The speed of a D.C. shunt motor can be increased by

1. increasing the resistance in armature circuit
2. increasing the resistance in field circuit
3. reducing the resistance in the field circuit
4. reducing the resistance in the armature circuit

15. The speed of a D.C. shunt motor is required to be more than full load speed. This is possible by

1. reducing the field current
2. decreasing the armature current
3. increasing the armature current
4. increasing the excitation current

16. The speed of a D.C. shunt motor more than its full-load speed can be obtained by

1. decreasing the field current
2. increasing the field current
3. decreasing the armature current
4. increasing the armature current

17. The speed of a motor falls from 1100 r.p.m. at no-load to 1050 r.p.m. at rated load. The speed regulation of the motor is

1. 2.36%
2. 4.76%
3. 6.77%
4. 8.84%

18. The starting resistance of a D.C. motor is generally

1. low
2. around 500 Q
3. 1000 Q
4. infinitely large

19. The total losses in a well designed D.C. generator of 10 kW will be nearly

1. 100 W
2. 500 W
3. 1000 W
4. 1500 W

20. The type of D.C. motor used for shears and punches is

1. shunt motor
2. series motor
3. differential compoutid D.C. motor
4. cumulative compound D.C. motor