Electrical Machines A DC motor with armature resistance of 0.5 ohms is connected directly to a 230 Volt supply. If the armature is stationary then the current flowing through armature is 460 A. 340 A. 250 A. 570 A. 460 A. 340 A. 250 A. 570 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The power factor of an induction motor operating at no load will have a value around 0.9 lag 0.2 lead 0.2 lag unity 0.9 lag 0.2 lead 0.2 lag unity ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Commutation in a DC machine may be explained as a process by which electric current in a coil is reversed. how alternate flux affects the main field flux. by virtue of which emf is induced in the armature conductors. in which magnetic field is set up. by which electric current in a coil is reversed. how alternate flux affects the main field flux. by virtue of which emf is induced in the armature conductors. in which magnetic field is set up. 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, 3, 5 1, 2, 3, 4 2, 3, 4 1, 2, 5 1, 3, 5 1, 2, 3, 4 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field of a dc shunt motor gets opened while the motor is running, then the armature will oscillate about original speed as the mean speed motor will become slow. armature current will drop motor will attain dangerously high speed armature will oscillate about original speed as the mean speed motor will become slow. armature current will drop motor will attain dangerously high speed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Field divertor method of speed control of a DC series motor gives speed above rated one due to reduction of Armature current. Field current. Line current. None of above. Armature current. Field current. Line current. None of above. ANSWER DOWNLOAD EXAMIANS APP
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