Electrical Machines Maximum allowable tan - delta (tanδ) of dielectric dispassion factor of power transformer insulating oil is generally taken as 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. 3 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature resistance of the dc motor is generally of the range 0.5 ohm. 100 ohm. 50 ohm. 0.1 ohm. 0.5 ohm. 100 ohm. 50 ohm. 0.1 ohm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer the magnetic coupling between the primary and secondary winding can be increased by using soft material for winding. using the magnetic core of low reluctance. using transformer oil of better quality. increasing the number of turns. using soft material for winding. using the magnetic core of low reluctance. using transformer oil of better quality. increasing the number of turns. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following DC Motor the ratio of starting torque to full load torque is minimum? Cumulative compound motor. Differential compound motor. Shunt motor. Series motor. Cumulative compound motor. Differential compound motor. Shunt motor. Series motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following alternators contain large number of poles? Turbo alternators. None of these Aame in both alternators. Hydro alternators. Turbo alternators. None of these Aame in both alternators. Hydro alternators. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For satisfactory parallel operation of two transformers which of the following conditions is most essential, MVA rating of all transformer inversely proportional to impedance. percentage impedance of all transformers must be same. voltage ratio of all transformers must be same. polarities of all transformers must be same. MVA rating of all transformer inversely proportional to impedance. percentage impedance of all transformers must be same. voltage ratio of all transformers must be same. polarities of all transformers must be same. ANSWER DOWNLOAD EXAMIANS APP