Electrical Machines What happens if fifth multiples of harmonics is given to induction motor? Fail to start. It will rotates in reverse direction. It will rotates in normal operation. Either short circuit or open circuit occurs. Fail to start. It will rotates in reverse direction. It will rotates in normal operation. Either short circuit or open circuit occurs. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-φ alternator has negligible stator resistance. A short circuit test is conducted on this alternator. At a particular speed, a field current of If1 is required to drive the rated armature current. If the speed of the alternator is reduced to half, the field current required to maintain rated armature current Would be equal to If1/2. Woud be equal to 2If1. Would be equal to If1. Cannot be predicted due to insufficient data. Would be equal to If1/2. Woud be equal to 2If1. Would be equal to If1. Cannot be predicted due to insufficient data. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage of a certain transformer is increased by 50% and the frequency is reduced by 50%, the maximum flux density will (assuming that the magnetic circuit remains unsaturated) changes to three times the original value remain the same as the original changes to 1.5 times the original value changes to 0.5 times the original value changes to three times the original value remain the same as the original changes to 1.5 times the original value changes to 0.5 times the original value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator the emf generated by the armature is maximum when induced voltage is high. shaft rotation is high. rate of change of flux is maximum. rate of change of flux is minimum. induced voltage is high. shaft rotation is high. rate of change of flux is maximum. rate of change of flux is minimum. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In star-delta starting of squirrel cage induction motor compared to DOL starting the starting current and torque are 1/3, 1/√3 1/√3, 1/√3 1/√3, 1/3 1/3, 1/3 1/3, 1/√3 1/√3, 1/√3 1/√3, 1/3 1/3, 1/3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Hysteresis loss is proportional to f. f1.5. f2. f3. f. f1.5. f2. f3. ANSWER DOWNLOAD EXAMIANS APP
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