MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 13 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Machines knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
At synchronous speed, relative speed between rotating air-gap flux and damper is? |
| A. | zero |
| B. | Ns |
| C. | lesser than Ns |
| D. | more than zero |
| Answer» B. Ns | |
| 2. |
Damper winding should have ___________ |
| A. | high resistance |
| B. | low starting torque |
| C. | low resistance |
| D. | low reactance |
| Answer» D. low reactance | |
| 3. |
Turbo generators do not use damper winding due to ___________ |
| A. | solid steel rotor core |
| B. | laminated armature |
| C. | soft iron core |
| D. | small current flow in pole shoes |
| Answer» B. laminated armature | |
| 4. |
The damper winding are placed in ___________ |
| A. | pole shoes |
| B. | series with armature |
| C. | series with field |
| D. | rotor slots |
| Answer» B. series with armature | |
| 5. |
Damper windings are made of ___________ |
| A. | copper |
| B. | iron |
| C. | silicon |
| D. | cast iron |
| Answer» B. iron | |
| 6. |
Employment of damper winding will reduce hunting. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 7. |
Using a _____ can be used to limit hunting. |
| A. | Flywheel |
| B. | DC Exciter |
| C. | Large load |
| D. | Any of the mentioned |
| Answer» E. | |
| 8. |
What are the probable causes of hunting? |
| A. | sudden change in load |
| B. | fault in supply |
| C. | sudden change in field current |
| D. | all of the mentioned |
| Answer» E. | |
| 9. |
Effects of hunting are/is ___________ |
| A. | mechanical stress |
| B. | surge in current |
| C. | rise in temperature |
| D. | all of the mentioned |
| Answer» E. | |
| 10. |
Variation of load angle delta, with loading of an unloaded synchronous motor with damping is? |
| A. | <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q4a.png"><img alt="Variation of load angle delta of unloaded synchronous motor with damping - option a" class="alignnone size-full wp-image-160961" height="203" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q4a.png" width="300"/></a> |
| B. | <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3a.png"><img alt="Variation of load angle delta of unloaded synchronous motor with damping - option b" class="alignnone size-full wp-image-160957" height="188" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3a.png" width="300"/></a> |
| C. | <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3c.png"><img alt="Variation of load angle delta of unloaded synchronous motor with damping - option c" class="alignnone size-full wp-image-160959" height="197" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3c.png" width="300"/></a> |
| D. | <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3d.png"><img alt="Variation of load angle delta of unloaded synchronous motor with damping - option d" class="alignnone size-full wp-image-160960" height="181" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3d.png" width="300"/></a> |
| Answer» B. <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3a.png"><img alt="Variation of load angle delta of unloaded synchronous motor with damping - option b" class="alignnone size-full wp-image-160957" height="188" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3a.png" width="300"/></a> | |
| 11. |
Variation of load angle delta, after sudden loading of an unloaded synchronous motor with no damping is? |
| A. | <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3a.png"><img alt="Variation of load angle delta of unloaded synchronous motor with no damping - option a" class="alignnone size-full wp-image-160957" height="188" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3a.png" width="300"/></a> |
| B. | <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3b.png"><img alt="Variation of load angle delta of unloaded synchronous motor with no damping - option b" class="alignnone size-full wp-image-160958" height="174" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3b.png" width="300"/></a> |
| C. | <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3c.png"><img alt="Variation of load angle delta of unloaded synchronous motor with no damping - option c" class="alignnone size-full wp-image-160959" height="197" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3c.png" width="300"/></a> |
| D. | <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3d.png"><img alt="Variation of load angle delta of unloaded synchronous motor with no damping - option d" class="alignnone size-full wp-image-160960" height="181" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3d.png" width="300"/></a> |
| Answer» B. <a href="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3b.png"><img alt="Variation of load angle delta of unloaded synchronous motor with no damping - option b" class="alignnone size-full wp-image-160958" height="174" src="https://www.sanfoundry.com/wp-content/uploads/2017/05/electrical-machines-interview-questions-answers-freshers-q3b.png" width="300"/></a> | |
| 12. |
The satisfactory operation of the synchronous machine means ___________ |
| A. | mechanical speed of rotor is equal to stator field speed |
| B. | mechanical speed is zero |
| C. | stator field is stationary |
| D. | none of the mentioned |
| Answer» B. mechanical speed is zero | |
| 13. |
The relative speed between rotor and stator field is zero. This means ___________ |
| A. | mechanical speed of rotor is equal to stator field speed |
| B. | mechanical speed is zero |
| C. | stator field is stationary |
| D. | none of the mentioned |
| Answer» B. mechanical speed is zero | |