| 1. | ln an alternator zero power factor method is used to find the ? | |
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synchronous impedance
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efficiency
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armature resistance
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voltage regulation
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Report Question| 2. | The permissible duration for which a generator of rated frequency 50 Hz can run at 46 Hz is ? | |
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one cycle
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one second
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one minute
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zero
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| 3. | H the driving power from the prime mover driving an alternator is lost but the alternator remains connected to the supply network and field supply is on, then the alternator will ? | |
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behave as an induction motor but will rotate in an opposite direction
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behave as a synchronous motor and will rotate in the same direction
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get burnt
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none of the above
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| 4. | The load between two steam-driven alternators operating in parallel may be adjusted by varying ? | |
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steam supply to their prime movers
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speed of the alternators
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field strengths of the alternators
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power factors of the alternators
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| 5. | What is the largest size of alternator being manufactured in India ? | |
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600MW
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260MW
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210 MW
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110MW
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| 6. | Non-salient pole type of rotor construction is usually provided in the alternators used in ? | |
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hydropower stations
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thermal power stations
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either of the above
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none of the above
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| 7. | In an alternator short pitch coils are used ? | |
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to reduce the stray losses
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to reduce the size of the machine
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to provide accurate phase difference of 120º between each phase
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reduce the harmonics in generated e.m.f.
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| 8. | Modern 3-phase alternator of a central power station will have generated voltage of ? | |
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132 k7
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11 kV
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400 V
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230 V
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| 9. | The rotor preferred for alternators applied to hydraulic turbines are ? | |
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salient pole type
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cylindrical rotor type
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solid rotor type
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any of the above
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| 10. | Two alternators '1' and '2' are-sharing' an inductive load equally. If the excitation of alternator '1' is increased ? | |
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alternator '2' will deliver less current and alternator 'l' will deliver more current
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alternator '2' will deliver more current and alternator '1' will deliver less current
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both will deliver more current
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both will continue to share load equally
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