Electrical Machines Armature reaction in dc motor results decrease in speed. increase in speed. open circuit. short circuit. decrease in speed. increase in speed. open circuit. short circuit. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following transformer insulating oil generally used in India? Aromatics based insulating oil. Olefin based insulating oil. Naphtha based insulating oil. Paraffin based insulating oil. Aromatics based insulating oil. Olefin based insulating oil. Naphtha based insulating oil. Paraffin based insulating oil. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For 250 volt DC Shunt Motor the armature and field resistance are 0.5 ohm and 250 ohm respectively. What will be the back e.m.f. produced when it takes a load current of 21A. 220 V. 150 V. 240 V. 280 V. 220 V. 150 V. 240 V. 280 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The introduction of interpoles in between the main poles improves the performance of a dc machine, because the interpoles produce additional flux to augment the developed torque a counter-emf is induced in the coil undergoing commutation the flux waveform is improved with reduction in harmonics the inequality of air-gap flux on the top and bottom halves of the armature is removed the interpoles produce additional flux to augment the developed torque a counter-emf is induced in the coil undergoing commutation the flux waveform is improved with reduction in harmonics the inequality of air-gap flux on the top and bottom halves of the armature is removed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Field weakening method is also called as-----------? constant torque control constant power control constant voltage control constant current control constant torque control constant power control constant voltage control constant current control ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC motor with armature resistance of 0.5 ohms connected directly to a 220 Volt supply. If the armature is stationary then the current flowing through the armature is 570 A. 440 A. 340 A. 250 A. 570 A. 440 A. 340 A. 250 A. ANSWER DOWNLOAD EXAMIANS APP