Electrical Machines The brush-axis of a bipolar dc motor is rotated by 90°. The effect of this rotation on the back emf Eband the torque developed Tdwould be such that both Eb and Td are zero both Eb and Td are unchanged Eb is unchanged, but Td is zero Eb is zero, but Td is unchanged both Eb and Td are zero both Eb and Td are unchanged Eb is unchanged, but Td is zero Eb is zero, but Td is unchanged ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The compensating winding in a DC machine is located in armature slots for compensation of the armature reaction. is located on pole shoes for avoiding the flashover at the commutator. is located on pole shoes to avoid the sparking at the brushes. is located on commutating poles for improving commutation. is located in armature slots for compensation of the armature reaction. is located on pole shoes for avoiding the flashover at the commutator. is located on pole shoes to avoid the sparking at the brushes. is located on commutating poles for improving commutation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The total core loss of a 400 V, 50 Hz transformer is 2400W, when it is supplied by 200 V, 25 Hz loss is 800W. Calculate eddy current loss and hysteresis loss? 1600W, 800W 1000W , 1400W 1400W, 1000W 800W, 1600W 1600W, 800W 1000W , 1400W 1400W, 1000W 800W, 1600W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A generator may loose residual magnetism due to over excitation. heating. any of these. vibrations. over excitation. heating. any of these. vibrations. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The magnetic field which initially induces emf in the armature in a self excited DC generator is because of permanent magnets. armature reaction. None of these residual magnetism. permanent magnets. armature reaction. None of these residual magnetism. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Oil is provided in an oil filled transformer for cooling. insulating. lubrication. both cooling and insulation. cooling. insulating. lubrication. both cooling and insulation. ANSWER DOWNLOAD EXAMIANS APP
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