Electrical Machines A 4 pole lap wound dc generator has 4 brushes, if one of the brush is damaged, what will be the change in V, I and P ratings V/2, I/2 and P/4 V, I and P V/2, I and P/2 V, I/2 and P/2 V/2, I/2 and P/4 V, I and P V/2, I and P/2 V, I/2 and P/2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines It is an advisable to use auto transformer if the transformation ratio is near to 1. Greater than 1. 0.5. 0.25. near to 1. Greater than 1. 0.5. 0.25. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Interpoles in a DC motor must be Series excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machines, the interpoles are provided to make commutation spark less. to counteract the reactance voltage and the cross-magnetizi both (B) and (C). to counteract demagnetizing effect of armature mmf in commutating zone. to make commutation spark less. to counteract the reactance voltage and the cross-magnetizi both (B) and (C). to counteract demagnetizing effect of armature mmf in commutating zone. ANSWER DOWNLOAD EXAMIANS APP
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. 65.8 Nm. 38.5 Nm. 74 Nm. 27.73 Nm . 65.8 Nm. 38.5 Nm. 74 Nm. 27.73 Nm . ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cogging in induction motor occurs when number of stator teeth - number of rotor teeth = even number. number of stator teeth - number of rotor teeth = 0. number of stator teeth - number of rotor teeth = negative number. number of stator teeth - number of rotor teeth = odd number. number of stator teeth - number of rotor teeth = even number. number of stator teeth - number of rotor teeth = 0. number of stator teeth - number of rotor teeth = negative number. number of stator teeth - number of rotor teeth = odd number. ANSWER DOWNLOAD EXAMIANS APP
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