1. The peak factor is the ratio of
Answer : A. peak value to RMS value
Explanation:-
2. A series RLC circuit has a resonant frequency of f0 Hz.If all the circuit element values are doubled, the new resonant frequency is _____
Answer : D. 0.5f0
Explanation:-
3. A three phase balanced delta connected circuit has a load impedance of (6+j9) ohms per phase. what is its equivalent star connected load impedance per phase in ohms?
Answer : B. (2+j3)
Explanation:-
4. If two wattmenter method of measurement of power, if the two wattmeters readings are equal, then the power factor will be
Answer : B. unity
Explanation:-
5. A step-up transformer increases _______
Answer : A. voltage
Explanation:-
6. A transformer having 1000 primary turns is connected to a 250V AC supply. For a secondary voltage of 400v, the number of secondary turns should be ______
Answer : D. 1600
Explanation:-
7. The equivalent resistance of the primary of a 220V/1100V transformer is 0.1ohm. Its equivalent resistance referred to secondary is _____
Answer : D. 2.5ohm
Explanation:-
8. A 100KVA transformer has an iron loss of 900w and full load copper loss of 1600w.Its load KVA corresponding to maximum efficiency is ______
Answer : C. 75 KVA
Explanation:-
9. If two transformers A and B are operating in parallel, with voltage rating of transformer A is slightly greater than that of transformer B. If Ea and Eb are induced emf's, Za and Zb are the impedances of transformers A and B then the circulating current Ic is given by _____
Answer : A. (Ea-Eb)/(Za+Zb)
Explanation:-
10. The phase shift in a star-star connected three phase transformer is ______
Answer : A. 0 degrees
Explanation:-
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