Electrical Machines Which of the following is/are the advantages of carbon brush over the copper brush? They are self lubricating in nature All of these They are not hard as copper brush In case of any sparking they will be less damaged than copper brushes They are self lubricating in nature All of these They are not hard as copper brush In case of any sparking they will be less damaged than copper brushes ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The material used for commutator brushes is mostly cast iron. mica. copper. carbon. cast iron. mica. copper. carbon. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The dc motor which can provide zero speed regulation at full load without any controller, is shunt. differential compound. series. cumulative compound. shunt. differential compound. series. cumulative compound. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The effect of ------------------ on main field flux is armature reaction? armature flux armature mmf armature current All of these armature flux armature mmf armature current All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An ideal synchronous motor has no starting torque because rotor winding is highly reactive. rotor is made up of salient poles. relative velocity between stator and rotor mmf’s is not zero. relative velocity between the stator and rotor mmf’s is zero. rotor winding is highly reactive. rotor is made up of salient poles. relative velocity between stator and rotor mmf’s is not zero. relative velocity between the stator and rotor mmf’s is zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An electric motor with constant output power will have a torque speed characteristics in the form of a Rectangular hyperbola Straight line parallel to the speed axis. Circle about the origin. Straight line through the origin. Rectangular hyperbola Straight line parallel to the speed axis. Circle about the origin. Straight line through the origin. ANSWER DOWNLOAD EXAMIANS APP