a) High at low loads and low at high loads b) Low at low loads and low at high loads c) Varies at low loads and constant at high loads d) Same at all loads Ans: (d)
a) Increases the weight per kW b) Increases the weight per kVA c) Decreases the weight per kVA d) Decreases the weight per kW Ans: (c)
a) About the same b) Much higher c) Much smaller d) Slightly higher Ans: (b)
a) 60° b) 45° c) 30° d) 80° Ans: (d)
a) Has core of stainless steel b) Has no losses and magnetic leakage c) Has a common core for its primary and secondary windings d) Has inter leaved primary and secondary windings Ans: (b)
a) In phase with each other b) Antiphase with each other c) Of different frequency d) Equal in magnitude Ans: (a)
a) Full load b) No load c) 50% of full load d) 75% of full load Ans: (c)
a) Eddy current losses b) Hysteresis losses c) Both eddy current and hysteresis losses d) Noise generated in the transformer Ans: (b)
a) High resistivity and high hysteresis loss b) High resistivity and low hysteresis loss c) Low resistivity and high hysteresis loss d) Low resistivity and low hysteresis loss Ans: (b)
a) Zero b) 100% c) 50% d) None of these Ans: (a)