Electrical Machines The short circuit test on a transformer is conducted to obtain eddy current loss. hysteresis loss. core loses only. copper losses. eddy current loss. hysteresis loss. core loses only. copper losses. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Wave winding is employed in DC machine of high current and low voltage rating. high current and low voltage rating. low current and low voltage rating. low current and high voltage rating. high current and low voltage rating. high current and low voltage rating. low current and low voltage rating. low current and high voltage rating. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motors, there is large decrease in maximum power factor when the dispersion coefficient is ________________. remains same. decreased. kept constant to certain value. increased. remains same. decreased. kept constant to certain value. increased. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine, which of these parameters remain the same whether it runs as a DC motor or a DC generator? Can not be determined. Mechanical power. Induced emf. Armature current. Can not be determined. Mechanical power. Induced emf. Armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Transformer action requires a increasing magnetic flux. alternating magnetic lux. alternating electric flux. constant magnetic flux. increasing magnetic flux. alternating magnetic lux. alternating electric flux. constant magnetic flux. 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%. 940 RPM 970 RPM 920 RPM 960 RPM 940 RPM 970 RPM 920 RPM 960 RPM ANSWER DOWNLOAD EXAMIANS APP