Electrical Machines In dc machines, the space distribution of air-gap flux density wave at no load is rectangular co- sinusoidal flat-topped sinusoidal rectangular co- sinusoidal flat-topped sinusoidal ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following factors improve commutation in a dc machine ? 1. High contact resistance of brushes 2. High inductance of the coils undergoing commutation 3. Shifting of brushes in the direction of rotation for a generator and in the opposite direction For a motor 4. Narrow width for the commutation bars Select the correct answer using the codes given below : Codes : 2, 3 and 4 1, 2, and 3 1, 2 and 4 1 and 3 2, 3 and 4 1, 2, and 3 1, 2 and 4 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following methods are used to control the speed of DC motors is armature circuit resistance control supply voltage control field current control All of these armature circuit resistance control supply voltage control field current control All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Ratio of starting torque to full load torque is minimum in Differential compound motor. Series motor. Shunt motor. Cumulative compound motor. Differential compound motor. Series motor. Shunt motor. Cumulative compound motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Flux density under trailing pole tips in case of generator will either increase or decrease decrease None of these increase either increase or decrease decrease None of these increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer zero voltage regulation is achieved at a load power factor which is lagging leading zero unity lagging leading zero unity ANSWER DOWNLOAD EXAMIANS APP
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