MCQOPTIONS
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MCQOPTIONS
This section includes 19 Mcqs, each offering curated multiple-choice questions to sharpen your Design Electrical Machines knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The no load power factor is the ratio of full load current to no load current. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 2. |
What is the formula for the mmf required for stator teeth? |
| A. | mmf required for stator teeth = mmf per metre + depth of stator slots |
| B. | mmf required for stator teeth = mmf per metre * depth of stator slots |
| C. | mmf required for stator teeth = mmf per metre / depth of stator slots |
| D. | mmf required for stator teeth = mmf per metre – depth of stator slots |
| Answer» C. mmf required for stator teeth = mmf per metre / depth of stator slots | |
| 3. |
What is the formula for mmf for air gap? |
| A. | mmf for air gap = 800000 * air gap flux density * air gap factor * length of air gap |
| B. | mmf for air gap = 800000 / air gap flux density * air gap factor * length of air gap |
| C. | mmf for air gap = 800000 * air gap flux density / air gap factor * length of air gap |
| D. | mmf for air gap = 800000 * air gap flux density * air gap factor / length of air gap |
| Answer» B. mmf for air gap = 800000 / air gap flux density * air gap factor * length of air gap | |
| 4. |
The flux is distributed sinusoidally and the mmf varies sinusoidally in a DC Machine. |
| A. | true |
| B. | false |
| Answer» C. | |
| 5. |
WHAT_IS_THE_FORMULA_FOR_MMF_FOR_AIR_GAP??$ |
| A. | mmf for air gap = 800000 * air gap flux density * air gap factor * length of air gap |
| B. | mmf for air gap = 800000 / air gap flux density * air gap factor * length of air gap |
| C. | mmf for air gap = 800000 * air gap flux density / air gap factor * length of air gap |
| D. | mmf for air gap = 800000 * air gap flux density * air gap factor / length of air gap |
| Answer» B. mmf for air gap = 800000 / air gap flux density * air gap factor * length of air gap | |
| 6. |
What is the formula for the mmf required for stator teeth?$ |
| A. | stator teeth mmf = mmf per metre / length of flux path in rotor core |
| B. | stator teeth mmf = mmf per metre + length of flux path in rotor core |
| C. | stator teeth mmf = mmf per metre * length of flux path in rotor core |
| D. | stator teeth mmf = mmf per metre – length of flux path in rotor core |
| Answer» D. stator teeth mmf = mmf per metre ‚Äö√Ñ√∂‚àö√ë‚àö¬® length of flux path in rotor core | |
| 7. |
What_is_the_formula_for_the_mmf_required_for_stator_teeth?$ |
| A. | mmf required for stator teeth = mmf per metre + depth of stator slots |
| B. | mmf required for stator teeth = mmf per metre * depth of stator slots |
| C. | mmf required for stator teeth = mmf per metre / depth of stator slots |
| D. | mmf required for stator teeth = mmf per metre – depth of stator slots |
| Answer» C. mmf required for stator teeth = mmf per metre / depth of stator slots | |
| 8. |
The no load power factor is the ratio of full load current to no load current? |
| A. | true |
| B. | false |
| Answer» B. false | |
| 9. |
What is the no load current percent of the full load current for the output of 37 KW? |
| A. | 50% |
| B. | 30% |
| C. | 27% |
| D. | 67% |
| Answer» C. 27% | |
| 10. |
What is the no load current percent of the full load current for the output of 0.75 KW? |
| A. | 50% |
| B. | 40% |
| C. | 33% |
| D. | 90% |
| Answer» B. 40% | |
| 11. |
What is the formula for the magnetizing current per phase? |
| A. | magnetizing current per phase =( 0.427 * no. of poles * total magnetizing mmf per pole ) / stator winding factor * no of turns of stator slots |
| B. | magnetizing current per phase =( 0.427 / no. of poles * total magnetizing mmf per pole ) / stator winding factor * no of turns of stator slots |
| C. | magnetizing current per phase =( 0.427 * no. of poles / total magnetizing mmf per pole ) / stator winding factor * no of turns of stator slots |
| D. | magnetizing current per phase =( 0.427 * no. of poles * total magnetizing mmf per pole ) * stator winding factor * no of turns of stator slots |
| Answer» B. magnetizing current per phase =( 0.427 / no. of poles * total magnetizing mmf per pole ) / stator winding factor * no of turns of stator slots | |
| 12. |
At what angle with respect to the interpolar axis does the flux tube gives a good approximation? |
| A. | 300 |
| B. | 450 |
| C. | 600 |
| D. | 900 |
| Answer» D. 900 | |
| 13. |
When maximum values of the design factors are considered, what is the relation between flux and the magnetizing current? |
| A. | flux is directly proportional to the magnetizing current |
| B. | flux is indirectly proportional to the magnetizing current |
| C. | flux is directly proportional to square of the magnetizing current |
| D. | flux is indirectly proportional to square of the magnetizing current |
| Answer» C. flux is directly proportional to square of the magnetizing current | |
| 14. |
What factors does the value of magnetizing current depend on? |
| A. | flux tube |
| B. | output power |
| C. | mean mmf |
| D. | mean mmf and flux tube |
| Answer» E. | |
| 15. |
The flux is distributed sinusoidally and the mmf varies sinusoidally in a DC Machine? |
| A. | true |
| B. | false |
| Answer» C. | |
| 16. |
How many parts does the flux produced by stator mmf passes through? |
| A. | 3 |
| B. | 4 |
| C. | 5 |
| D. | 6 |
| Answer» D. 6 | |
| 17. |
How is the Magnetizing component with respect to the voltage? |
| A. | the magnetizing component is in phase with the voltage |
| B. | the magnetizing component is 900 leading the voltage |
| C. | the magnetizing component is 900 lagging the voltage |
| D. | the magnetizing component is 900 out of phase with the voltage |
| Answer» E. | |
| 18. |
How many components does the no load current characteristics comprise of? |
| A. | 2 |
| B. | 3 |
| C. | 4 |
| D. | 1 |
| Answer» B. 3 | |
| 19. |
How many methods are present to obtain all the machine performance characteristics? |
| A. | 3 |
| B. | 2 |
| C. | 1 |
| D. | 4 |
| Answer» C. 1 | |