Electrical Machines A 4 pole 50 Hz induction motor is running at 1470 rpm. Find the speed of stator magnetic field with respect to rotor? 1470 rpm zero 30 rpm 1500 rpm 1470 rpm zero 30 rpm 1500 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If peak value of phase mmf is F max , then peak value of the rotating field caused by three phase is Fmax. (1/2)Fmax. (3/2)Fmax. 3Fmax. Fmax. (1/2)Fmax. (3/2)Fmax. 3Fmax. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Compensating winding are used to rectify the flux density waveform at region under main pole. None of these throughout the air gap. interpole region. region under main pole. None of these throughout the air gap. interpole region. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For satisfactory parallel operation of two transformers which of the following conditions is most essential, MVA rating of all transformer inversely proportional to impedance. percentage impedance of all transformers must be same. polarities of all transformers must be same. voltage ratio of all transformers must be same. MVA rating of all transformer inversely proportional to impedance. percentage impedance of all transformers must be same. polarities of all transformers must be same. voltage ratio of all transformers must be same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The demagnetising component of armature reaction in a DC generator results in sparking trouble. increases armature speed. reduces generator emf. reduces inter poles flux density. results in sparking trouble. increases armature speed. reduces generator emf. reduces inter poles flux density. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In circle diagram for induction motor, diameter of circle represents which of the following ? Slip. Running torque. Rotor current. Line voltage. Slip. Running torque. Rotor current. Line voltage. ANSWER DOWNLOAD EXAMIANS APP
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