A. copper loss becomes high in proportion to the output
B. iron loss is increased considerably
C. voltage drop both in primary and secondary becomes large
D. secondary output is much less as compared to primary input
Related Mcqs:
- A transformer cannot raise or lower the voltage of a D.C. supply because_______________?
A. there is no need to change the D.C. voltage
B. a D.C. circuit has more losses
C. Faraday’s laws of electromagnetic induction are not valid since the rate of change of flux is zero
D. none of the above - Which of the following is the main advantage of an auto-transformer over a two winding transformer?
A. Hysteresis losses are reduced
B. Saving in winding material
C. Copper losses are negligible
D. Eddy losses are totally eliminated - 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 efficiency of a transformer will be maximum when_____________?
A. copper losses = hysteresis losses
B. hysteresis losses = eddy current losses
C. eddy current losses = copper losses
D. copper losses = iron losses - Efficiency of a power transformer is of the order of________________?
A. 100 per cent
B. 98 per cent
C. 50 per cent
D. 25 per cent - In a transformer routine efficiency depends upon_____________?
A. supply frequency
B. load current
C. power factor of load
D. both B. and (c) - The maximum efficiency of a distribution transformer is____________?
A. at no load
B. at 50% full load
C. at 80% full load
D. at full load - An ideal transformer will have maximum efficiency at a load such that?
A. copper loss = iron loss
B. copper loss iron loss
D. none of the above - 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 - The secondary of a current transformer is always short-circuited under operating conditions because it____________________?
A. avoids core saturation and high voltage induction
B. is safe to human beings
C. protects the primary circuit
D. none of the above
