A. hysteresis and eddy current losses
B. friction and windage losses
C. copper losses
D. none of the above
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Related Mcqs:
- In a given transformer for given applied voltage, losses which remain constant irrespective of load changes are______________?
- A. friction and windage losses B. copper losses C. hysteresis and eddy current losses D. none of the above...
- For given applied voltage, with the increase in frequency of the applied voltage?
- A. eddy current loss will decrease B. eddy current loss will increase C. eddy current loss will remain unchanged D. none of the above...
- The no load current in a transformer lags behind the applied voltage by an angle of about_____________?
- A. 180° B. 120″ C. 90° D. 75°...
- In an actual transformer the iron loss remains practically constant from no load to full load because:____________?
- A. value of transformation ratio remains constant B. permeability of transformer core remains constant C. core flux remains practically constant D. primary voltage remains constant C. secondary voltage remains constant...
- 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?
- A. Conservator B. Breather C. Bushings D. Buchholz relay...
- The no-load current drawn by transformer is usually what per cent of the full-load current ?
- A. 0.2 to 0.5 per cent B. 2 to 5 per cent C. 12 to 15 per cent D. 20 to 30 per cent...
- For a transformer, operating at constant load current, maximum efficiency will occur at______________?
- A. 0.8 leading power factor B. 0.8 lagging power factor C. zero power factor D. unity power factor...
- When a given transformer is run at its rated voltage but reduced frequency, its____________?
- A. flux density remains unaffected B. iron losses are reduced C. core flux density is reduced D. core flux density is increased...
- Auto-transformer makes effective saving on copper and copper losses, when its transformation ratio is_________________?
- A. approximately equal to one B. less than one C. great than one D. none of the above...
- Reduction in core losses and increase in permeability are obtained with transformer employing__________?
- A. core built-up of laminations of cold rolled grain oriented steel B. core built-up of laminations of hot rolled sheet C. either of the above D. none of the above...
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