Electrical Machines A 4 pole dynamo with wave wound armature has 51 slots contains 20 conductors in each slot. If induced emf 357 Volts and speed is 8500 rpm, flux per pole will be 1.2 mWb. 2.7 mWb. 3.5 mWb. 1.4 mWb. 1.2 mWb. 2.7 mWb. 3.5 mWb. 1.4 mWb. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the synchronous reactance of alternators in which a given field current of 200 A on short circuit and a generated emf of 50 V on open circuit. Armature resistance is 0.1 ohm 0.5Ω. 0.23Ω. 1Ω. 0.25Ω. 0.5Ω. 0.23Ω. 1Ω. 0.25Ω. 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 Consider the following statements: To control the speed of a dc shunt motor above the base speed over a reasonably wide range, the motor must 1. have compensating winding 2. have interpole winding 3. be started using a 3-point starter 4. be started using a 4-point starter Of these statements 1 and 3 are correct 2 and 4 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct 1 and 3 are correct 2 and 4 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two windings provided on the stator of 1-phase induction motor, one main winding and the other auxiliary winding are connected either of these depending on the design of the motor through inductive coupling in parallel in series either of these depending on the design of the motor through inductive coupling in parallel in series ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is minimized by laminating the core of a transformer? Eddy current loss. Copper loss. Stray loss. Hysteresis loss. Eddy current loss. Copper loss. Stray loss. Hysteresis loss. ANSWER DOWNLOAD EXAMIANS APP
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