Electrical Machines The speed regulation of a DC motor is given as (NfL − NnL)/NnL. (NnL − NfL)/NfL. NnL/NfL. NnL − NfL. (NfL − NnL)/NnL. (NnL − NfL)/NfL. NnL/NfL. NnL − NfL. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The no load current in a transformer lags the applied voltage by 90°. 0°. about 115°. about 75°. 90°. 0°. about 115°. about 75°. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When excitation is increased (over excitation), the synchronous generator operates at any of the above. leading power factor. unity power factor. lagging power factor. any of the above. leading power factor. unity power factor. lagging power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor when started on no load does not accelerate up to full speed but runs at 1/7th of the rated speed. The motor is said to be plugging. cogging. crawling. locking. plugging. cogging. crawling. locking. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by the armature of DC motor is directly proportional to The speed of motor. The voltage across the terminals. The torque required. None of above. The speed of motor. The voltage across the terminals. The torque required. None of above. 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
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