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 28 W. 25 W. 30 W. 36 W. 28 W. 25 W. 30 W. 36 W. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is minimized by laminating the core of a transformer? Copper loss. Stray loss. Eddy current loss. Hysteresis loss. Copper loss. Stray loss. Eddy current loss. Hysteresis loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If starter is not used with large DC motor for starting, it will provide execessive voltage drop in line. damage the armature and commutator. all of above. draw a starting current many times its rated full load current. provide execessive voltage drop in line. damage the armature and commutator. all of above. draw a starting current many times its rated full load current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following windings are necessary in case of all dc machines? closed winding lap winding open type winding wave winding closed winding lap winding open type winding wave winding 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, 3, 6 2, 4, 5, 6 3, 4, 5 1, 2, 5 2, 3, 6 2, 4, 5, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When an electric train is moving down a hill, the DC motor will operate as DC shunt motor. DC series generator. DC series motor. DC shunt generator. DC shunt motor. DC series generator. DC series motor. DC shunt generator. ANSWER DOWNLOAD EXAMIANS APP