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 25 W. 28 W. 30 W. 36 W. 25 W. 28 W. 30 W. 36 W. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator sparking between brushes and commutator surface may be due to over commutation. under commutation. too rapid reversal of current. any of the above. over commutation. under commutation. too rapid reversal of current. any of the above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For 250 volt DC Shunt Motor the armature and field resistance are 0.5 ohm and 250 ohm respectively. What will be the back e.m.f. produced when it takes a load current of 21A. 150 V. 280 V. 220 V. 240 V. 150 V. 280 V. 220 V. 240 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : 1. interpole windings are connected in series with armature windings 2. polarity of interpoles must be the same as that of the main poles in advance 3. distortion of the main field under the pole shoes is not affected by the use of interpoles From above, the correct answer is 1 and 3 1 and 2 1 alone 2 and 3 1 and 3 1 and 2 1 alone 2 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor is expensive for same Kw output rates? Induction motor. Synchronous motor. AC single phase motor. DC Shunt Motor Induction motor. Synchronous motor. AC single phase motor. DC Shunt Motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Ward Leonard control is provides speed control Above rated speed. In both direction. Below rated speed. In one direction only. Above rated speed. In both direction. Below rated speed. In one direction only. ANSWER DOWNLOAD EXAMIANS APP