Transformers The efficiency of a transformer, under heavy loads, is comparatively low because copper loss becomes high in proportion to the output iron loss is increased considerably voltage drop both in primary and secondary becomes large secondary output is much less as compared to primary input copper loss becomes high in proportion to the output iron loss is increased considerably voltage drop both in primary and secondary becomes large secondary output is much less as compared to primary input ANSWER DOWNLOAD EXAMIANS APP
Transformers The no load ratio of a 50 Hz single phase transformer is 6000/250 V. The maximum flux in the core is 0.06 Wb. What is the number of primary turns? 450 350 210 900 450 350 210 900 ANSWER DOWNLOAD EXAMIANS APP
Transformers Which of the following transformer is smallest? 2kVA, 200 Hz 2kVA, 50 Hz 2kVA, 500 Hz 2kVA, 400 Hz 2kVA, 200 Hz 2kVA, 50 Hz 2kVA, 500 Hz 2kVA, 400 Hz ANSWER DOWNLOAD EXAMIANS APP
Transformers The approximate efficiency of a large transformer is 80% 95% 65% 50% 80% 95% 65% 50% ANSWER DOWNLOAD EXAMIANS APP
Transformers In Ns is the synchronous speed and s the slip, then actual running speed of an induction motor will be (l-s)Ns s.N. Ns (Ns-l)s (l-s)Ns s.N. Ns (Ns-l)s ANSWER DOWNLOAD EXAMIANS APP
Transformers Which of the following is the main advantage of an auto-transformer over a two winding transformer? Copper losses are negligible Eddy losses are totally eliminated Saving in winding material Hysteresis losses are reduced Copper losses are negligible Eddy losses are totally eliminated Saving in winding material Hysteresis losses are reduced ANSWER DOWNLOAD EXAMIANS APP
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