Electrical Machines Which of the following is/are the advantages of carbon brush over the copper brush? All of these In case of any sparking they will be less damaged than copper brushes They are self lubricating in nature They are not hard as copper brush All of these In case of any sparking they will be less damaged than copper brushes They are self lubricating in nature They are not hard as copper brush 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 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 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. Series 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 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. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC motor with armature resistance of 0.5 ohms connected directly to a 220 Volt supply. If the armature is stationary then the current flowing through the armature is 570 A. 440 A. 250 A. 340 A. 570 A. 440 A. 250 A. 340 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generators brushes are used for reduce eddy current loss collecting of voltage collecting of current without any sparkings convert ac armature current in to dc reduce eddy current loss collecting of voltage collecting of current without any sparkings convert ac armature current in to dc ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer has hysteresis loss of 30 W, at 240 V, 60 Hz. The hysteresis loss at 200 V, 50 Hz will be 36 W. 28 W. 25 W. 30 W. 36 W. 28 W. 25 W. 30 W. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which motors are preferred for refrigeration and air conditioning in smaller units? Induction motors. Universal motors. Reluctance motors. Stepper motors. Induction motors. Universal motors. Reluctance motors. Stepper motors. ANSWER DOWNLOAD EXAMIANS APP