Electrical Machines Maximum allowable tan - delta (tanδ) of dielectric dispassion factor of power transformer insulating oil is generally taken as 3 at 90°C. 0.5 at 90°C. 2 at 90°C. 1 at 90°C. 3 at 90°C. 0.5 at 90°C. 2 at 90°C. 1 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC machine is a conduction machine. convection machine. none of above are correct. both are correct. conduction machine. convection machine. none of above are correct. both are correct. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3-phase induction motor, torque and supply voltage are related as T ∝ 1/V² T ∝ 1/V T∝ V² T ∝ V T ∝ 1/V² T ∝ 1/V T∝ V² T ∝ V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In large sized DC machines the compensating windings are provided to neutralize voltage induced in coil due to fluctuation of l compensate for the decrease in speed due to increase of load. reduce eddy current losses by providing local short circuits. None of these neutralize voltage induced in coil due to fluctuation of l compensate for the decrease in speed due to increase of load. reduce eddy current losses by providing local short circuits. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following voltage regulator is preferred for providing large values of load current? None of these Zener diode shunt regulator. Transistor shunt regulator. Transistor series regulator. None of these Zener diode shunt regulator. Transistor shunt regulator. Transistor series regulator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 2, 3, 6 1, 2, 5 2, 4, 5, 6 3, 4, 5 2, 3, 6 1, 2, 5 2, 4, 5, 6 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
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