MCQOPTIONS
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MCQOPTIONS
This section includes 9 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. |
The total losses in a well-designed DC generator of 10 kW will be nearly equal to ________ |
| A. | 100 W |
| B. | 500 W |
| C. | 1000 W |
| D. | 1500 W |
| Answer» C. 1000 W | |
| 2. |
Which of the following losses are significantly reduced by laminating the core of a DC generator? |
| A. | Hysteresis losses |
| B. | Eddy current losses |
| C. | Copper losses |
| D. | Windage losses |
| Answer» C. Copper losses | |
| 3. |
Which of the following loss/losses in a DC generator is dissipated in the form of heat? |
| A. | Mechanical loss |
| B. | Core loss |
| C. | Copper loss |
| D. | Mechanical, Copper and Core |
| Answer» E. | |
| 4. |
Which of the following methods is likely to result in reduction of hysteresis loss in a DC generator? |
| A. | Providing laminations in armature core |
| B. | Providing laminations in stator |
| C. | Using non-magnetic material for frame |
| D. | Using material of low hysteresis co-efficient for armature core material |
| Answer» E. | |
| 5. |
Which of the following loss in a DC generator varies significantly with the load current? |
| A. | Field copper loss |
| B. | Windage loss |
| C. | Armature copper loss |
| D. | Cannot be determined |
| Answer» D. Cannot be determined | |
| 6. |
Which of the following loss is likely to have highest proportion at rated load of the DC generator? |
| A. | Hysteresis loss |
| B. | Field copper loss |
| C. | Armature copper loss |
| D. | Eddy current loss |
| Answer» D. Eddy current loss | |
| 7. |
Which of the following is not the effect of iron loss? |
| A. | Loss of efficiency |
| B. | Excessive heating of core |
| C. | Increase in terminal voltage |
| D. | Rise in temperature of ventilating air |
| Answer» D. Rise in temperature of ventilating air | |
| 8. |
The hysteresis loss in a DC machine least depends on _____________ |
| A. | Frequency of magnetic reversals |
| B. | Maximum value of flux density |
| C. | Volume and grade of iron |
| D. | Rate of flow of ventilating air |
| Answer» E. | |
| 9. |
The efficiency of the DC motor at maximum power will be ___________________ |
| A. | 100% |
| B. | Around 90% |
| C. | Anywhere between 75% and 90% |
| D. | Less than 50% |
| Answer» E. | |