| 1. | ln turbo-alternators, smooth cylindrical type rotors used have long axial length because ? | |
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it gives smooth running of the rotor
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it reduces windage loss
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centrifugal force is reduced
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number of armature conductors being less, they have to be necessarily long for generating the required voltage
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Report Question| 2. | Salient pole type rotors as compared to cylindrical pole type are ? | |
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small in diameter as well as axial length
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large in diameter as well as axial length
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smaller in diameter and larger in axial length
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larger in diameter and smaller in axial length
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| 3. | Synchronous impedance method of finding voltage regulation of an alternator is called pessimistic method because ? | |
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it is simplest to perform: and compute
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it gives regulation value higher than is actually found by direct loading
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armature reaction is wholly magnetising
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none of the above
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| 4. | ..... plays an important role in over speed protection of a generator ? | |
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Governor
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Differential protection
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Over current relay
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Alarm
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| 5. | Voltage regulation obtained by synchronous impedance method is ? | |
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equal to that given by actual tests
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less than that given by actual tests
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more than that given by actual tests
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none of the above
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| 6. | If the input to the prime mover of an alternator is kept constant but the excitation is changed then ? | |
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the power factor of the load remains constant
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the reactive component of the output is changed
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the active component of the output is changed
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none of the above
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| 7. | Large-diameter salient-pole rotors have short axial length mainly because ? | |
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it occupies much less space
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it reduces rotor weight
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number of armature conductors held in the large circumference rotor being very large, they need not belong
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it saves lot of copper in stator winding
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| 8. | One of the super-thermal power stations is being located at ? | |
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Panipat
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Haridwar
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Farraka
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U.P.
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| 9. | For parallel operation, A.C. polypbase alternators must have the same ? | |
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kVA rating
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excitation
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speed
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voltage rating
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| 10. | Which of the following methods is best for finding the voltage regulation ? | |
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Synchronous impedance method
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M.M.F. method
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Potier triangle method
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All are equally good
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