MCQOPTIONS
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MCQOPTIONS
This section includes 16 Mcqs, each offering curated multiple-choice questions to sharpen your Dc Machines knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
How total number of brushes in a commutator are determined in a given DC machine? |
| A. | Speed of armature |
| B. | Type of winding |
| C. | Voltage |
| D. | Amount of current to be collected |
| Answer» E. | |
| 2. |
In case of DC machine winding, number of commutator segments is equal to ______ |
| A. | Number of armature coils |
| B. | Number of armature coil sides |
| C. | Number of armature conductors |
| D. | Number of armature turns |
| Answer» B. Number of armature coil sides | |
| 3. |
Which conductors are in point of contact with brushes? |
| A. | Lie under south pole |
| B. | Lie under north pole |
| C. | Lie in inter polar region |
| D. | Are farthest from the poles |
| Answer» D. Are farthest from the poles | |
| 4. |
What are the number of the brushes in the wave winding? |
| A. | Same or more than the number of poles |
| B. | Same or less than the number of poles |
| C. | Exactly half the number of poles |
| D. | Depends on other parameters |
| Answer» B. Same or less than the number of poles | |
| 5. |
In DC generators, current is fed up to the external circuit from armature through _______ |
| A. | Commutator |
| B. | Direct wire |
| C. | Slip rings |
| D. | Cannot be determined |
| Answer» B. Direct wire | |
| 6. |
WHICH_CONDUCTORS_ARE_IN_POINT_OF_CONTACT_WITH_BRUSHES??$ |
| A. | Lie under south pole |
| B. | Lie under north pole |
| C. | Lie in inter polar region |
| D. | Are farthest from the poles |
| Answer» D. Are farthest from the poles | |
| 7. |
How total number of brushes in a commutator are determined in a given DC machine?$ |
| A. | Speed of armature |
| B. | Type of winding |
| C. | Voltage |
| D. | Amount of current to be collected |
| Answer» E. | |
| 8. |
In case of DC machine winding, number of commutator segments is equal to ______$ |
| A. | Number of armature coils |
| B. | Number of armature coil sides |
| C. | Number of armature conductors |
| D. | Number of armature turns |
| Answer» B. Number of armature coil sides | |
| 9. |
In DC generators, current is fed up to the external circuit from armature through ______? |
| A. | Commutator |
| B. | Direct wire |
| C. | Slip rings |
| D. | Cannot be determined |
| Answer» B. Direct wire | |
| 10. |
When Copper brushes are used in DC machine? |
| A. | Where low voltage and high currents are involved |
| B. | Where high voltage and small currents are involved |
| C. | Cannot be determined |
| D. | Where low voltage and low currents are involved |
| Answer» B. Where high voltage and small currents are involved | |
| 11. |
What are the number of the brushes in the lap winding? |
| A. | Double the number of poles |
| B. | Same as the number of poles |
| C. | Half the number of poles |
| D. | Two |
| Answer» C. Half the number of poles | |
| 12. |
In D.C. generators, rapid brush ware causes due to _________ |
| A. | Severe sparking |
| B. | Rough commutator surface |
| C. | Imperfect contact |
| D. | Severe sparking, rough commutator surface or imperfect contact |
| Answer» E. | |
| 13. |
Which of the following method is used to connect commutator segments to armature conductors? |
| A. | Brazing |
| B. | Normal wires |
| C. | Insulation pads |
| D. | Copper lugs |
| Answer» E. | |
| 14. |
Commutator performs rectification so that output of the machine is bi-directional. |
| A. | True |
| B. | False |
| Answer» C. | |
| 15. |
In a DC machine, rectification provided with commutator is ___________ |
| A. | Half wave rectification |
| B. | Full wave rectification |
| C. | Semi controlled rectification |
| D. | Uncontrolled rectification |
| Answer» C. Semi controlled rectification | |
| 16. |
The armature in DC machines is always placed on rotor because _______ |
| A. | Otherwise commutation will not be possible |
| B. | Otherwise there will not be any induced emf |
| C. | Otherwise current will not flow |
| D. | Can be placed anywhere |
| Answer» B. Otherwise there will not be any induced emf | |