Electrical Machines Motors for fans and pumps are selected in the rpm range 500 to 720. 375 to 500. 1440 to 2880. 720 to 920. 500 to 720. 375 to 500. 1440 to 2880. 720 to 920. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines How can the synchronous speed of a 3 - Φ IM be varied? By varying number of poles. By varying supply voltage. By varying the supply frequency. Both (A) and (B). By varying number of poles. By varying supply voltage. By varying the supply frequency. Both (A) and (B). ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To eliminate the 5th harmonic in the induced voltages their respective pitch factor angle should be 18° 30° 72° 36° 18° 30° 72° 36° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the reactance voltage when current is changed from -2A to 2A in 4 sec and self inductance is 1H? 1 V 4 V 0 V 2 V 1 V 4 V 0 V 2 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, the ripples in the direct emf generated are reduced by employing carbon brushes. commutator with large number of segments. equalizer rings. graphite brushes. carbon brushes. commutator with large number of segments. equalizer rings. graphite brushes. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Under operating conditions the rotor conductor should be _________________ in induction motor. always opened. semi closed or semi opened. none. always closed. always opened. semi closed or semi opened. none. always closed. ANSWER DOWNLOAD EXAMIANS APP