Electrical Machines A 4 pole DC generator runs at 750 rpm and generate an emf of 240 V. The armature is wave wound and has 792 conductors. If the total flux from each pole is 0.0145 Wb. What is the leakage co-efficient? 1.5. 1.2. 1.4. 1.8. 1.5. 1.2. 1.4. 1.8. 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 In a loaded DC generator, if the brushes are given a shift from the interpolar axis in the direction of rotation, then the commutation will deteriorate with rise in terminal voltage. deteriorate with fall of terminal voltage. improve with fall of terminal voltage. improve with rise in terminal voltage. deteriorate with rise in terminal voltage. deteriorate with fall of terminal voltage. improve with fall of terminal voltage. improve with rise in terminal voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the armature current of 5 Amp is flowing through the dc motor the torque produced is 47 Nm. Keeping the speed constant if the armature current is increased to 7 amp, calculate the new torque. Assume losses to be constant. 74 Nm. 65.8 Nm. 27.73 Nm . 38.5 Nm. 74 Nm. 65.8 Nm. 27.73 Nm . 38.5 Nm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer OC test is conducted on HV side and SC test is conducted on LV side OC test is conducted on LV side and SC test is conducted on HV side both OC and SC tests are conducted on LV side both Oc and SC tests are conducted on HV side OC test is conducted on HV side and SC test is conducted on LV side OC test is conducted on LV side and SC test is conducted on HV side both OC and SC tests are conducted on LV side both Oc and SC tests are conducted on HV side ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is the largest conversion device? DC machine Synchronous machine Induction machine All of these DC machine Synchronous machine Induction machine All of these ANSWER DOWNLOAD EXAMIANS APP
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