| 1. | If two alternators are running in proper synchronism and the voltage of one machine is suddenly increased ? | |
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both machines will stop
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one machine will stop
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synchronising torque will be produced to restore further synchronism
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none of the above
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Report Question| 2. | ln an alternator field the effect of cross magnetisation is to make the output ? | |
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non-sinusoidal
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true sinusoidal
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free from harmonics
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none of the above
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| 3. | An alternator is capable of delivering power at a particular efficiency. The frequency can be increased by ? | |
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reversing the armature rotation
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reversing the field polarity
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increasing the current supplied to the field electromagnets
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increasing the armature speed
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| 4. | Zero power factor method for an alternator is generally used to determine ? | |
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synchronous impedance of alternator
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efficiency of alternator
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voltage regulation of the alternator
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none of the above
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| 5. | If an alternator is operating at leading power factor, then it can be concluded that ? | |
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the alternator is under-excited
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the alternator is over-excited
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the torque angle of the alternator has negative value
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the residual magnetism of the poles is zero
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| 6. | The power factor of an alternator is determined by its ? | |
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primemover
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excitation
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speed
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load
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| 7. | Voltage regulation of an alternator is usually ? | |
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equal to that of power transformer
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much lower than that of a power transformer
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much higher than that of a power transformer
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none
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| 8. | Dirt accumulation in generators can cause ? | |
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flashovers
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overheating
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poor voltage regulation
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all of the above
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| 9. | The fictitious part of synchronous reactance takes care of ? | |
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inductive reactance
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armature reaction
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voltage regulation
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none of the above
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| 10. | Overheating of generator's winding ? | |
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reduces life of the machine
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does not have any significant effect
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reduces generated voltage
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reduces power factor
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