Electrical Machines If the full load speed of 3-phase, 50Hz induction motor is 950 rpm, what is its half load speed nearly equals to? 1000 rpm 940 rpm 950 rpm 975 rpm 1000 rpm 940 rpm 950 rpm 975 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V dc machine has an armature resistance of 1Ω.If the full-load current is 20 A, the differenc in the induced voltages when the machine is running as a motor and as a generator is 50 V zero 40 V 20 V 50 V zero 40 V 20 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4-pole DC generator runs at 1500 rpm. The frequency of current in the armature winding is: 50 Hz. 100 Hz. Zero Hz. 25 Hz. 50 Hz. 100 Hz. Zero Hz. 25 Hz. 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%. 960 RPM 970 RPM 940 RPM 920 RPM 960 RPM 970 RPM 940 RPM 920 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The overall power factor of an on load transformer is always lagging. is always leading. depends on the power factor of the load. is always unity. is always lagging. is always leading. depends on the power factor of the load. is always unity. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The basic function of a transformer is to change the level of the voltage the power level the power factor the frequency the level of the voltage the power level the power factor the frequency ANSWER DOWNLOAD EXAMIANS APP