Electrical Machines Armature coil is short circuited by brushes when it lies along field axis. along neutral axis. in none of above positions. in any of above positions. along field axis. along neutral axis. in none of above positions. in any of above positions. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 1, 2, 5 2, 3, 6 3, 4, 5 2, 4, 5, 6 1, 2, 5 2, 3, 6 3, 4, 5 2, 4, 5, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine, for the same value of Æ, Z and N; which one of the following statements is correct? Armature emf is more with wave winding than with lap winding. Armature emf depends on weather the machine is running as a motor or generator. Armature emf is less with wave winding than with lap winding. Armature emf is same as long as the flux density in the air gap remains the same. Armature emf is more with wave winding than with lap winding. Armature emf depends on weather the machine is running as a motor or generator. Armature emf is less with wave winding than with lap winding. Armature emf is same as long as the flux density in the air gap remains the same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a single phase transformer the magnitude of leakage reactance is twice that of resistance of both primary and secondary. With secondary short circuited, the input power factor is 1/√5 1/√2 2/√5 1/3 1/√5 1/√2 2/√5 1/3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc machine, the demagnetizing effect of armature reaction is due to magnetic saturation in half of the field pole non-sinusoidal nature of armature mmf uneven air-gap length component of armature mmf along field axis magnetic saturation in half of the field pole non-sinusoidal nature of armature mmf uneven air-gap length component of armature mmf along field axis ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Total core loss is also called as -------------? Copper loss Eddy current loss Magnetic loss Hysteresis loss Copper loss Eddy current loss Magnetic loss Hysteresis loss ANSWER DOWNLOAD EXAMIANS APP