Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm and rotor input power is 2KW. Find the rotor copper loss? 40W 100W 80W 60W 40W 100W 80W 60W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The flux involved in the emf equation of a transformer has average value. total value. rms value. maximum value. average value. total value. rms value. maximum value. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The following statements relate to compensating winding (CW) and interpole winding (IW) of a dc machine : 1. CW neutralizes the armature reaction under a pole pitch 2. IW is connected in series with armature circuit 3. IW produces mmf in the commutating zone only 4. CWmmf is directed along the brush axis 5. Mmf produced by IW is equal to armature mmf From these, the correct statements are 2, 3, 4 1, 2, 3, 4 and 5 1, 3, 4, 5 2, 3, 4, 5 2, 3, 4 1, 2, 3, 4 and 5 1, 3, 4, 5 2, 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machines, the interpoles are provided to make commutation spark less. both (B) and (C). to counteract demagnetizing effect of armature mmf in commutating zone. to counteract the reactance voltage and the cross-magnetizi to make commutation spark less. both (B) and (C). to counteract demagnetizing effect of armature mmf in commutating zone. to counteract the reactance voltage and the cross-magnetizi ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, the ripples in the direct emf generated are reduced by employing carbon brushes. graphite brushes. equalizer rings. commutator with large number of segments. carbon brushes. graphite brushes. equalizer rings. commutator with large number of segments. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC generator will not build up voltage if field resistance is more than critical resistance. any one of above. due to wrong direction of rotation. if it has lost residual magnetism. if field resistance is more than critical resistance. any one of above. due to wrong direction of rotation. if it has lost residual magnetism. ANSWER DOWNLOAD EXAMIANS APP
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