Electrical Machines In DC machines, the interpoles are provided both (B) and (C). to make commutation spark less. to counteract the reactance voltage and the cross-magnetizi to counteract demagnetizing effect of armature mmf in commutating zone. both (B) and (C). to make commutation spark less. to counteract the reactance voltage and the cross-magnetizi to counteract demagnetizing effect of armature mmf in commutating zone. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Normally for the design of transformer the ambient temperature is taken as 35°C. 27°C. 45°C. 32°C. 35°C. 27°C. 45°C. 32°C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of a compensated DC series motor, the compensating winding is provided In parallel with the armature winding. In parallel with the field winding. As a separate unit. In series with the armature winding. In parallel with the armature winding. In parallel with the field winding. As a separate unit. In series with the armature winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the necessity of copper brushes in a dc motors? None of these. To absorb the mechanical shocks produced during running condition. To increase the flux cutting by the rotor. To convert alternating supply current to direct current. None of these. To absorb the mechanical shocks produced during running condition. To increase the flux cutting by the rotor. To convert alternating supply current to direct current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An ideal synchronous motor has no starting torque because relative velocity between stator and rotor mmf’s is not zero. rotor winding is highly reactive. rotor is made up of salient poles. relative velocity between the stator and rotor mmf’s is zero. relative velocity between stator and rotor mmf’s is not zero. rotor winding is highly reactive. rotor is made up of salient poles. relative velocity between the stator and rotor mmf’s is zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the frequency of a alternator, if P = number of poles and N = revolution made per second? 120 / PN Hz. 120P / N Hz. PN / 2 Hz. 120N / P Hz. 120 / PN Hz. 120P / N Hz. PN / 2 Hz. 120N / P Hz. ANSWER DOWNLOAD EXAMIANS APP