Electrical Machines A smaller air gap in a polyphase induction motor helps to reduce the magnetizing current. reduce the chance of cogging. reduce the chance of crawling. increase the starting torque. reduce the magnetizing current. reduce the chance of cogging. reduce the chance of crawling. increase the starting torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer maximum flux density is not constant, the eddy current loss varies as V f f² V² V f f² V² ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Hunting in a synchronous motor takes place when load varies. motor is under loaded. when supply voltage fluctuates. when power factor is unity. when load varies. motor is under loaded. when supply voltage fluctuates. when power factor is unity. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, 1. reactance voltage is proportional to armature current 2.reactance voltage is proportional to core length 3.reactance voltage is due to self-flux of the coil undergoing commutation 4. armature-cross flux is neutralized by interpolar flux 5. interpolarmmf is more than armature mmf in the interpolar zone From these, the correct answer is 1, 2, 3, 4 1, 2, 5 1, 3, 5 2, 3, 4 1, 2, 3, 4 1, 2, 5 1, 3, 5 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of these types of motor is used in elevators? DC compound motor. None of these. DC shunt motor. DC series motor. DC compound motor. None of these. DC shunt motor. DC series motor. 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 will both increase. The magnitude of current will decrease but the power factor will increase. The magnetude of current will increase, but power factor will decrease. The magnitude of circuit as well as the power factor will decrease. The magnitude will both increase. The magnitude of current will decrease but the power factor will increase. The magnetude of current will increase, but power factor will decrease. The magnitude of circuit as well as the power factor will decrease. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS