Electrical Machines When the armature current of 5 Amp is flowing through the dc motor the torque produced is 47 Nm. Keeping the speed constant if the armature current is increased to 7 amp, calculate the new torque. Assume losses to be constant. 38.5 Nm. 27.73 Nm . 74 Nm. 65.8 Nm. 38.5 Nm. 27.73 Nm . 74 Nm. 65.8 Nm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature resistance control method is also called as-----------? constant voltage control constant power control constant torque control constant current control constant voltage control constant power control constant torque control constant current control ANSWER DOWNLOAD EXAMIANS APP
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 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 both Eb and Td are zero ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For successful parallel operation of two single phase transformers, the most essential condition is that their polarities are properly connected KVA ratings are equal turn- ratios are exactly equal percentage impedances are equal polarities are properly connected KVA ratings are equal turn- ratios are exactly equal percentage impedances are equal ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The residual magnetism of a self-excited dc generator is lost. To build up its emf again the field winding must be replaced the field winding connection must be reversed field winding must be excited by low voltage dc supply the armature connection must be reversed the field winding must be replaced the field winding connection must be reversed field winding must be excited by low voltage dc supply the armature connection must be reversed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Hunting in a synchronous motor takes place motor is under loaded. when power factor is unity. when supply voltage fluctuates. when load varies. motor is under loaded. when power factor is unity. when supply voltage fluctuates. when load varies. ANSWER DOWNLOAD EXAMIANS APP