Electrical Machines Hopkinss test in DC motor is conducted at ? None of these. No load. Low load. Full load. None of these. No load. Low load. Full load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The introduction of interpoles in between the main poles improves the performance of a dc machine, because a counter-emf is induced in the coil undergoing commutation the flux waveform is improved with reduction in harmonics the interpoles produce additional flux to augment the developed torque the inequality of air-gap flux on the top and bottom halves of the armature is removed a counter-emf is induced in the coil undergoing commutation the flux waveform is improved with reduction in harmonics the interpoles produce additional flux to augment the developed torque the inequality of air-gap flux on the top and bottom halves of the armature is removed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous motor torque or load angle δ ------------- with increase in load decreases increases None of these remains unaffected decreases increases None of these remains unaffected ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The demagnetising component of armature reaction in a DC generator increases armature speed. reduces generator emf. results in sparking trouble. reduces inter poles flux density. increases armature speed. reduces generator emf. results in sparking trouble. reduces inter poles flux density. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A single phase transformer when supplied from 220 V, 50 Hz has eddy current loss of 50 W. If the transformer is connected voltage of 330 V, 75 Hz, the eddy current loss will be 112.5 W 168.75 W 50 W 75 W 112.5 W 168.75 W 50 W 75 W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC motors are stopped by opening line switches and not by forcing the handle of the motor starter back to OFF position. This is due to occurance of Heavy sparking at the first stud of starting resistance steps. Heavy sparking at brushes. Both of above. None of these. Heavy sparking at the first stud of starting resistance steps. Heavy sparking at brushes. Both of above. None of these. ANSWER DOWNLOAD EXAMIANS APP