Electrical Machines A commutator in dc machine provide ----------------- rectification? half wave controlled full wave controlled half wave full wave half wave controlled full wave controlled half wave full wave ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two 3-phase AC generators are such that one has twice the linear dimensions of the other. The field windings of each are excited to give identical sinusoidal air-gap flux density waveform. Both have the same number of stator slots and identical winding patterns. The conductor/slot in a big generator is K times that of the smaller one. The value of K to get equal no load voltage at same frequency is 1/2. 8. 1/4. 4. 1/2. 8. 1/4. 4. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a three phase star - delta transformer, what is the angle difference between primary and secondary phase voltages? Star side leads by 30°. Delta side leads by 30°. Star side lags by -30°. Delta side lags by -30°. Star side leads by 30°. Delta side leads by 30°. Star side lags by -30°. Delta side lags by -30°. 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 920 RPM 970 RPM 960 RPM 940 RPM 920 RPM 970 RPM 960 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines As compared to an induction motor, the air gap in a DC motor is more. same. less than 50%. between 50% and 90%. more. same. less than 50%. between 50% and 90%. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The voltmeter connected across a generator reads voltage same at no load and at full load (rated). The generator is of the type level compound. series generator. shunt generator. short - shunt generator. level compound. series generator. shunt generator. short - shunt generator. ANSWER DOWNLOAD EXAMIANS APP