Electrical Machines In a DC generator the emf generated by the armature is maximum when rate of change of flux is maximum. shaft rotation is high. rate of change of flux is minimum. induced voltage is high. rate of change of flux is maximum. shaft rotation is high. rate of change of flux is minimum. induced voltage is high. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of generated emf in the armature coil of a DC machine is 1. the same as that of the current in a generator 2. the same as that of the current in a motor 3. opposite to that of the current in a generator 4. opposite to that of the current in a motor From these, the correct answer is 2, 4 1, 4 2, 3 1, 3 2, 4 1, 4 2, 3 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Short circuit test is performed on a transformer with a certain impressed voltage at rated frequency. If the short circuit test is now performed with the same magnitude of impressed voltage, but at frequency higher than the rated frequency then The magnitude of current will decrease but the power factor will increase. The magnitude will both increase. The magnitude of circuit as well as the power factor will decrease. The magnetude of current will increase, but power factor will decrease. The magnitude of current will decrease but the power factor will increase. The magnitude will both increase. The magnitude of circuit as well as the power factor will decrease. The magnetude of current will increase, but power factor will decrease. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm. Find the rotor efficiency? 92% 94% 96% 95% 92% 94% 96% 95% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If starting current of a 3 - Φ induction motor is 5 times the rated current, while rated slip is 4 %, then ratio of starting torque to full load torque is 0.8. 0.6. 0.4. 1. 0.8. 0.6. 0.4. 1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 2 pole, 12 slot synchronous machine is operating at synchronous speed. Find the slot angle? 60° 18° 20° 30° 60° 18° 20° 30° ANSWER DOWNLOAD EXAMIANS APP
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