Electrical Machines In a transformer the magnetic coupling between the primary and secondary winding can be increased by using the magnetic core of low reluctance. using soft material for winding. increasing the number of turns. using transformer oil of better quality. using the magnetic core of low reluctance. using soft material for winding. increasing the number of turns. using transformer oil of better quality. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, the ripples in the direct emf generated are reduced by employing graphite brushes. equalizer rings. carbon brushes. commutator with large number of segments. graphite brushes. equalizer rings. carbon brushes. commutator with large number of segments. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-φ alternator has negligible stator resistance. A short circuit test is conducted on this alternator. At a particular speed, a field current of If1 is required to drive the rated armature current. If the speed of the alternator is reduced to half, the field current required to maintain rated armature current Woud be equal to 2If1. Would be equal to If1. Cannot be predicted due to insufficient data. Would be equal to If1/2. Woud be equal to 2If1. Would be equal to If1. Cannot be predicted due to insufficient data. Would be equal to If1/2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor is more expensive for same KW output rating ? Synchronous motor. Induction motor. DC Shunt Motor AC single phase motor. Synchronous motor. Induction motor. DC Shunt Motor AC single phase motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following rotor requires damper winding? Salient pole rotor. Both type rotor. Cylindrical rotor. None of these Salient pole rotor. Both type rotor. Cylindrical rotor. None of these 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 maximum and Rf minimum Ra maximum and Rf maximum Ra minimum and Rf minimum Rf maximum and Ra minimum Ra maximum and Rf minimum Ra maximum and Rf maximum Ra minimum and Rf minimum Rf maximum and Ra minimum ANSWER DOWNLOAD EXAMIANS APP
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