Electrical Machines Hysteresis loop represents the area of total iron losses eddy current loss hysteresis loss copper loss total iron losses eddy current loss hysteresis loss copper loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A voltmeter gives 120 oscillations per minute when connected to the rotor of an induction motor. The frequency is 50Hz. The slip of the motor is 5% 25% 2% 4% 5% 25% 2% 4% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The efficiency of a transformer is mainly dependent on copper losses. dielectric losses. stray losses. core losses. copper losses. dielectric losses. stray losses. core losses. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An 8 pole DC generator has 500 armature conductors and useful flux per pole of 0.065 Wb. What will be the emf generated if it is lap connected and runs at 1000 rpm. What must be the speed at which it is driven to produce the same emf if it is wave wound? 2166.67V, 230 rpm. 541.67V, 200 rpm. 541.67V, 250 rpm. 2166.67V, 270 rpm. 2166.67V, 230 rpm. 541.67V, 200 rpm. 541.67V, 250 rpm. 2166.67V, 270 rpm. 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 : 1 and 3 1, 2, and 3 1, 2 and 4 2, 3 and 4 1 and 3 1, 2, and 3 1, 2 and 4 2, 3 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC generator without commutator is a DC motor induction motor DC generator AC generator DC motor induction motor DC generator AC generator ANSWER DOWNLOAD EXAMIANS APP
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