Electrical Machines In a DC machine, the angle between the stator and rotor fields is 0o. dependent upon the load. 180o. 90o. 0o. dependent upon the load. 180o. 90o. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Hysteresis loss is proportional to f. f1.5. f3. f2. f. f1.5. f3. f2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider a separately excited DC motor. If the field current is increased while the armature terminal voltage is held constant, then speed of the motor None of these. Increase. Remains same. Decrease. None of these. Increase. Remains same. Decrease. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 3, 4, 5 1, 2, 5 2, 4, 5, 6 2, 3, 6 3, 4, 5 1, 2, 5 2, 4, 5, 6 2, 3, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Short circuiting is caused in the armature winding due to failure of insulation between two commutator bars. failure of insulation between two turns of coil. grounding of two or more turns of the same coil. any of above. failure of insulation between two commutator bars. failure of insulation between two turns of coil. grounding of two or more turns of the same coil. any of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if the field flux axis is ahead of the armature field axis in the direction of rotation, the machine operating is synchronous motor. asynchronous generator. asynchronous motor. synchronous generator. synchronous motor. asynchronous generator. asynchronous motor. synchronous generator. ANSWER DOWNLOAD EXAMIANS APP