Electrical Machines Under commutation results in no sparking. sparking the trailing edge of the brush. sparking at the middle of the brush. sparking at the leading edge of the brush. no sparking. sparking the trailing edge of the brush. sparking at the middle of the brush. sparking at the leading edge of the brush. 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, 3, 4 2, 3, 4 1, 3, 5 1, 2, 5 1, 2, 3, 4 2, 3, 4 1, 3, 5 1, 2, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor is expensive for same Kw output rates? AC single phase motor. Induction motor. Synchronous motor. DC Shunt Motor AC single phase motor. Induction motor. Synchronous motor. DC Shunt Motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The effect of ------------------ on main field flux is armature reaction? armature current armature mmf armature flux All of these armature current armature mmf armature flux All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The stator core of a 3 - Φ induction motor is laminated in order to reduce the eddy current loss. hysteresis loss. both of the above. weight of the stator. eddy current loss. hysteresis loss. both of the above. weight of the stator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Interpoles in a DC motor must be Shunt excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. ANSWER DOWNLOAD EXAMIANS APP