Electrical Machines The speed of a 50 Hz three phase induction motor under full load condition is 725 rpm the number of poles of the motor are ______________. 2. 6. 4. 8. 2. 6. 4. 8. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 1, 2, 3 2, 3, 4 2, 3, 4, 5 2, 3 ,5 1, 2, 3 2, 3, 4 2, 3, 4, 5 2, 3 ,5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The induction motor shaft is made of aluminium. mild steel. cast iron. stainless steel. aluminium. mild steel. cast iron. stainless steel. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the rotor of a 3 phase induction motor is blocked then the slip is 0.54. 1. 0.7. 0.3. 0.54. 1. 0.7. 0.3. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following machine is invariably provided with forced ventilation? Fractional horse power slow speed motor. Hermetically sealed motor of refrigerator. 50 MW generator in a power plant. Fractional horse power high speed motor. Fractional horse power slow speed motor. Hermetically sealed motor of refrigerator. 50 MW generator in a power plant. Fractional horse power high speed motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The introduction of interpoles in between the main poles improves the performance of a dc machine, because the flux waveform is improved with reduction in harmonics a counter-emf is induced in the coil undergoing commutation the interpoles produce additional flux to augment the developed torque the inequality of air-gap flux on the top and bottom halves of the armature is removed the flux waveform is improved with reduction in harmonics a counter-emf is induced in the coil undergoing commutation the interpoles produce additional flux to augment the developed torque the inequality of air-gap flux on the top and bottom halves of the armature is removed ANSWER DOWNLOAD EXAMIANS APP