| 1. | Transformer supplying load having negative resistance characteristics such as arc load, is considered if its voltage regulation is ? | |
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low
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high
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either of the above
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none of the above
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Report Question| 2. | Leakage fluxes of a transformer may be minimized by ? | |
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avoiding overloads
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keeping magnetizing current to the minimum
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reducing the reluctance of the iron core to the minimum
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sectionalizing and interleaving the primary and secondary windings
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| 3. | The yoke sections of transformers using hot-rolled laminations is made 15 per cent greater than that of the core so as to ? | |
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to increase the size of the transformers
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to reduce the copper loss
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to reduce the iron loss in yoke and magnetizing current
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to provide better cooling
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| 4. | ln Scott connections the main transformer has centre tap on ? | |
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primary winding
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secondary windings
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both primary and secondary windings
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none of the above
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| 5. | For transformers upto a capacity of ...... kVA air blast cooling is provided ? | |
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2500
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5000
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10000
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20000
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| 6. | The voltage transformation ratio of a transformer is equal to the ratio of ? | |
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primary turns to secondary turns
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secondary current to primary current
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secondary induced e.m.f. to primary induced e.m.f.
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secondary terminal voltage to primary applied voltage
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| 7. | Which of the following statements regarding an ideal single-phase transformer having a turn ratio of 1 : 2 and drawing a current of 10 A from 200 V A.C. supply is incorrect ? | |
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Its secondary current is 5 A
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Its secondary voltage is 400 V
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Its rating is 2 kVA
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Its secondary current is 20 A
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| 8. | Which of the following is not the standard voltage for power supply in India ? | |
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11 kV
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33 kV
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66 kV
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122kV
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| 9. | Iron loss of a transformer can be measured by ? | |
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low power factor wattmeter
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unity power factor wattmeter
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frequency meter
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any type of wattmeter
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| 10. | The changes in volume of transformer cooling oil due to variation of atmospheric temperature during day and night is taken care of by which part of transformer ? | |
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Conservator
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Breather
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Bushings
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Buchholz relay
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