| 1. | Which of the following prime-movers is the least efficient ? | |
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Steam turbine
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steam engine
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Gas turbine
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Diesel engine
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Report Question| 2. | Which of the following relays come into operation in the event of the failure of prime-mover connected to the generator ? | |
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Buchholz relay
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Reverse power relay
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Differential relay
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All of the above
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| 3. | Dirt accumulation, in generators can cause all of the following except ? | |
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low power factor
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poor voltage regulation
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flashovers
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overheating
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| 4. | In an alternator, pitch factor is the ratio of the e.m.fs. of ? | |
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full pitch winding to short pitch winding
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short pitch coil to full pitch coil
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distributed winding to full pitch winding
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full pitch winding to concentrated winding
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| 5. | ln a larger generator dampers ? | |
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reduce frequency fluctuations
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increase stability
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reduce voltage fluctuations
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none of the above
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| 6. | Alternators, now a days, are designed to have poor regulation because ? | |
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it re1uces the construction cost
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it limits the value of short circuit current
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we employ automatic voltage regulators
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none of the above
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| 7. | Excessive windage loss and noise occur with ? | |
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cylindrical rotors
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salient pole rotors
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either of the above
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none of the above
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| 8. | At leading power factor, the armature flux in an alternator ? | |
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distorts the rotor flux
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aids the rotor flux
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opposes the rotor flux
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does not affect the rotor flux
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| 9. | In large generators protection provided against external faults is ? | |
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inter-turn fault protection
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sensitive earth fault protection
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biased differential protection
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all of the above
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| 10. | A commercial alternator has ? | |
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stationary armature and rotary field
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rotating armature and stationary field
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both armature and field rotary
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both armature and field fixed
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