| 1. | Unlike D.C. generator kW rating, alternators are rated in ? | |
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MW
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kVAR
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kWh
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kVA
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Report Question| 2. | When the speed of an alternator increases ? | |
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the frequency decrease
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the frequency increases
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the frequency remains same
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the frequency changes
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| 3. | When two alternators are running in parallel, their kVAR load share are changed by changing their ? | |
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driving torque, driving torque respectively
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driving torque, excitation respectively
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excitation, driving torque respectively
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excitation and excitation
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| 4. | In an alternator, the frequency of voltage generated depends on ? | |
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rotative speed only
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number of poles only
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both (a) and (b)
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none of the above
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| 5. | Two alternators are running in parallel. if the field of one of the alternators is adjusted it will ? | |
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change its power factor
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change its frequency
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reduce its speed
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change its load
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| 6. | If the driving force of both the alternators running in parallel is changed. this will result in change in ? | |
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generated voltage
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frequency
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back e.m.f.
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all of the above
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| 7. | In an alternator one of the advantages of distributing the winding is to ? | |
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improve voltage waveform
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reduce noise
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save on copper
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reduce harmonics
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| 8. | Salient pole rotors are used where ? | |
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high frequency current is required
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floor space is available in plenty
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low and medium speed prime movers are available
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high speed prime movers are available
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| 9. | In an alternator if the armature reaction produces demagnetisation of the main field, the power factor should be ? | |
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unity
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zero, lagging load
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zero, leading load
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none of the above
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| 10. | Generated e.m.f. for same field current and double speed will be ? | |
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same
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double
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less than double
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more than double
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