Electrical Machines The armature reaction mmf in a DC machines has a form of sinusoidal. trapezoidal. rectangular. triangular. sinusoidal. trapezoidal. rectangular. triangular. 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. 280 V. 240 V. 150 V. 220 V. 280 V. 240 V. 150 V. 220 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The application that need frequent starting and stopping is lifts and hoists. jaw crushers. paper mills. blowers. lifts and hoists. jaw crushers. paper mills. blowers. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer has resistance and reactance in per unit as 0.01 and 0.04 respectively. Its voltage regulation for 0.8 power factor lagging and leading will be 4.8% and -3.2% 6% and -4% None of these 3.2% and -1.6% 4.8% and -3.2% 6% and -4% None of these 3.2% and -1.6% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines φA DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the speed when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 920 RPM 960 RPM 940 RPM 970 RPM 920 RPM 960 RPM 940 RPM 970 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is minimized by laminating the core of a transformer? Hysteresis loss. Eddy current loss. Stray loss. Copper loss. Hysteresis loss. Eddy current loss. Stray loss. Copper loss. ANSWER DOWNLOAD EXAMIANS APP