Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.573. 0.443. 0.512. 0.649. 0.573. 0.443. 0.512. 0.649. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Due to magnetic saturation, the flux per pole in a DC machine without brush shift decreases in generators and increases in motor with load. increases in both the generators and the motors with load. decreases in both generators and the motors with load. increases in generators but decreases in motor with load. decreases in generators and increases in motor with load. increases in both the generators and the motors with load. decreases in both generators and the motors with load. increases in generators but decreases in motor with load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cogging and crawling are phenomena associated with cage induction machines and they are essentially the same. the former during starting and the latter at a fraction of its rated speed. the former at a fraction of its rate speed and the latter during starting. any of the above. cage induction machines and they are essentially the same. the former during starting and the latter at a fraction of its rated speed. the former at a fraction of its rate speed and the latter during starting. any of the above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following motors DC excitation is not required? hysteresis motor 3-phase synchronous motor reluctance motor 3-phase synchronous generator hysteresis motor 3-phase synchronous motor reluctance motor 3-phase synchronous generator ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Dynamic braking is very effective for differential compound motors. shunt motors. series motors. separately excited motors. differential compound motors. shunt motors. series motors. separately excited motors. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Silicon content in steel lamination is kept within 5% as it increases hysteresis loss. makes the material brittle. Increases cost. All of these increases hysteresis loss. makes the material brittle. Increases cost. All of these ANSWER DOWNLOAD EXAMIANS APP