Electrical Machines When the mechanical power is developed by a DC motor maximum Back emf is equal. None of above. back emf is equal to applied voltage. Back emf is equal to half of applied voltage. Back emf is equal. None of above. back emf is equal to applied voltage. Back emf is equal to half of applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Satisfactory commutation of DC machine requires All of these brushes should be of proper grade and size. brushes should smoothly run in the holders. smooth, concentric commutator properly undercut. All of these brushes should be of proper grade and size. brushes should smoothly run in the holders. smooth, concentric commutator properly undercut. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 20KVA auto transformer, turn ratio is 0.8. Find the power transferred conductively? 16KVA 0KVA 4KVA 20KVA 16KVA 0KVA 4KVA 20KVA ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, 1. reactance voltage is proportional to armature current 2.reactance voltage is proportional to core length 3.reactance voltage is due to self-flux of the coil undergoing commutation 4. armature-cross flux is neutralized by interpolar flux 5. interpolarmmf is more than armature mmf in the interpolar zone From these, the correct answer is 1, 2, 5 1, 2, 3, 4 1, 3, 5 2, 3, 4 1, 2, 5 1, 2, 3, 4 1, 3, 5 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Silicon content in steel lamination is kept within 5% as it All of these makes the material brittle. Increases cost. increases hysteresis loss. All of these makes the material brittle. Increases cost. increases hysteresis loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of following winding is connected in series with armature winding of DC machine? Compensating winding. Auxiliary winding. Both Compensating and Commutating pole winding. Commutating pole winding. Compensating winding. Auxiliary winding. Both Compensating and Commutating pole winding. Commutating pole winding. ANSWER DOWNLOAD EXAMIANS APP