Electrical Machines In a 3 - Φ IM with line frequency f1 and winding factor kw1 and kw2 for stator and rotor respectively the ratio of per phase stator winding emf E1 to per phase rotor winding emf E2 at standstill is given by E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are effects of armature reaction? All of these increase the maintenance and repair increase the iron loss increases the design cost All of these increase the maintenance and repair increase the iron loss increases the design cost ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor is running with a divertor connected across its field winding. If the divertor resistance is reduced then the speed of the motor will decrease. increase. remain unaltered. become execessively high. decrease. increase. remain unaltered. become execessively high. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The short circuit test on a transformer is conducted to obtain copper losses. eddy current loss. hysteresis loss. core loses only. copper losses. eddy current loss. hysteresis loss. core loses only. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motors, there is large decrease in maximum power factor when the dispersion coefficient is ________________. increased. remains same. decreased. kept constant to certain value. increased. remains same. decreased. kept constant to certain value. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The mmf produced by rotor currents of a 3 - Φ induction motor rotates at synchronous speed with respect to rotor. is at standstill with respect to stator mmf. rotates at slip speed with respect to stator mmf. rotates at the speed of rotor in the air gap. rotates at synchronous speed with respect to rotor. is at standstill with respect to stator mmf. rotates at slip speed with respect to stator mmf. rotates at the speed of rotor in the air gap. ANSWER DOWNLOAD EXAMIANS APP
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