a) Alumimium b) Silicon steel c) Copper d) Wood Ans: (b)
a) Hysteresis loss b) Eddy current loss c) Heat loss d) All of these Ans: (b)
a) 0.35 mm to 0.5 mm b) 3.5 mm to 5 mm c) 35 mm to 50 mm d) 5mm to 10 mm Ans: (a)
a) Area of the core b) Flux density of core material c) Frequency d) Both (b) and (c) Ans: (d)
a) Provide insulation to the windings b) Provide cooling to the windings c) Take insulating oil from the con-servator d) Extract moisture from the air Ans: (d)
a) Drum placed at the bottom of the tank b) An air tight metal drum fixed at the top of the tank c) Overload protection circuit d) None of these Ans: (b)
a) Infinite b) Zero c) About 1 MΩ d) About 100 MΩ Ans: (a)
a) Square core section b) Stepped core section c) Rectangular core section d) None of these Ans: (b)
a) Hysteresis loss is less b) Permeability is higher c) Magnetic reluctance of the three phases can be balanced d) Eddy current loss is less Ans: (c)
a) Eddy current loss b) Insulation requirement c) Leakage fluxes d) Hysteresis loss Ans: (b)