Electrical Machines In a DC generator the emf generated by the armature is maximum when rate of change of flux is minimum. shaft rotation is high. induced voltage is high. rate of change of flux is maximum. rate of change of flux is minimum. shaft rotation is high. induced voltage is high. rate of change of flux is maximum. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An alternator is feeding an infinite busbar. Its prime mover is suddenly shutdown. The alternator will continue to work as alternator but the direction of rotation will reverse. start working as induction motor. continue to work as synchronous motor with same direction of rotation. come to stand still. continue to work as alternator but the direction of rotation will reverse. start working as induction motor. continue to work as synchronous motor with same direction of rotation. come to stand still. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt motor has external resistance Ra and Rf in the armature and field circuits respectively. Armature current at starting can be reduced by keeping Ra minimum and Rf minimum Ra maximum and Rf maximum Rf maximum and Ra minimum Ra maximum and Rf minimum Ra minimum and Rf minimum Ra maximum and Rf maximum Rf maximum and Ra minimum Ra maximum and Rf minimum ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a polyphase induction motor helps to reduce the magnetizing current. reduce the chance of cogging. increase the starting torque. reduce the chance of crawling. reduce the magnetizing current. reduce the chance of cogging. increase the starting torque. reduce the chance of crawling. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The effect of ------------------ on main field flux is armature reaction? armature current All of these armature mmf armature flux armature current All of these armature mmf armature flux ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a three phase star - delta transformer, what is the angle difference between primary and secondary phase voltages? Star side lags by -30°. Delta side leads by 30°. Star side leads by 30°. Delta side lags by -30°. Star side lags by -30°. Delta side leads by 30°. Star side leads by 30°. Delta side lags by -30°. ANSWER DOWNLOAD EXAMIANS APP