Electrical Machines The armature of DC motor is laminated to reduce the eddy current loss. to reduce the inductor. to reduce the hysteresis loss. to reduce the mass. to reduce the eddy current loss. to reduce the inductor. to reduce the hysteresis loss. to reduce the mass. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous motor when the rotor speed exceeds the synchronous speed during hunting the damper bars develop synchronous motor torque. the damper bars develop induction motor torque. the damper bars develop induction generator torque. negative sequence currents are generated. the damper bars develop synchronous motor torque. the damper bars develop induction motor torque. the damper bars develop induction generator torque. negative sequence currents are generated. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Induction motors provided with open slots have more breakdown torque. higher efficiency. less breakdown torque. leading power factor. more breakdown torque. higher efficiency. less breakdown torque. leading power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4-pole DC generator runs at 1500 rpm. The frequency of current in the armature winding is: 50 Hz. 25 Hz. Zero Hz. 100 Hz. 50 Hz. 25 Hz. Zero Hz. 100 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous motor hunting can be reduced to minimum possible by using a flywheel. providing damper winding in the rotor pole faces. any of above methods. designing the motor for adequate synchronizing power. using a flywheel. providing damper winding in the rotor pole faces. any of above methods. designing the motor for adequate synchronizing power. 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, 4, 5, 6 1, 2, 5 3, 4, 5 2, 3, 6 2, 4, 5, 6 1, 2, 5 3, 4, 5 2, 3, 6 ANSWER DOWNLOAD EXAMIANS APP
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