| 1. | Transformer for constant voltage applications is considered good if its voltage regulation is ? | |
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low
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high
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zero
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none of the above
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Report Question| 2. | ln a power transformer the efficiency should be maximum at ? | |
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50 % of full load
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60 % full load
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80 % full load
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full load
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| 3. | Helical coils are very well suited for ? | |
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low voltage winding of large rating transformers
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high voltage winding of small rating transformers
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high voltage winding of large rating transformers
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none of the above
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| 4. | In a transformer frictional loss is ? | |
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5% of total loss
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10% of total loss
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20% of total loss
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nil
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| 5. | A transformer is used to change the value of ? | |
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power factor
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power
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frequency
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voltage
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| 6. | Which of the following insulating materials can withstand the highest temperature safely ? | |
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Cellulose
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Asbestos
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Mica
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Glass fibre
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| 7. | Auto-transformer makes effective saving on copper and copper losses, when its transformation ratio is ? | |
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approximately equal to one
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less than one
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great than one
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none of the above
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| 8. | A current transformer is ? | |
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a magnetic component to change voltage level
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an instrument to transform A.C. current to D.C. current
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magnetic component to change current level
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none of the above
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| 9. | While rising and falling if a wave is not symmetrical, it contains ? | |
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even harmonics in addition to fundamental
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odd harmonics in addition to fundamental
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both odd and even harmonics in addition to fundamental
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none of the above
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| 10. | What is the typical use of an autotransformer ? | |
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Control transformer
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Isolating transformer
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Variable transformer
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Toy transformer
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