Electrical Machines The use of double squirrel cage winding on the rotor provides a large starting torque. reduced starting torque. low noise. higher efficiency. a large starting torque. reduced starting torque. low noise. higher efficiency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature reaction of an unsaturated DC machine is demagnetising. magnetising. crossmagnetising. none of above. demagnetising. magnetising. crossmagnetising. none of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In star-delta starting of squirrel cage induction motor compared to DOL starting the starting current and torque are 1/3, 1/√3 1/3, 1/3 1/√3, 1/3 1/√3, 1/√3 1/3, 1/√3 1/3, 1/3 1/√3, 1/3 1/√3, 1/√3 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 2, 3, 6 1, 2, 5 3, 4, 5 2, 4, 5, 6 2, 3, 6 1, 2, 5 3, 4, 5 2, 4, 5, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature core of the rotor bars of dc motors are laminated to reduce mechanical losses. to reduce hysteresis loss. to provide better flux linkage. to reduce eddy current loss. to reduce mechanical losses. to reduce hysteresis loss. to provide better flux linkage. to reduce eddy current loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole 50 Hz 1-phase induction motor is running at 1470 rpm. Find the forward and backward slips? 0.02, 1.98 0.02, 0.98 0.04, 0.96 0.04, 1.96 0.02, 1.98 0.02, 0.98 0.04, 0.96 0.04, 1.96 ANSWER DOWNLOAD EXAMIANS APP
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