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. 0.512. 0.573. 0.649. 0.443. 0.512. 0.573. 0.649. 0.443. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a step down transformer which one of the following statements is true? Secondary power is less than primary power. Number of secondary turns is more than that of primary. Secondary current is less than primary current. Number of secondary turns is less than primary turns. Secondary power is less than primary power. Number of secondary turns is more than that of primary. Secondary current is less than primary current. Number of secondary turns is less than primary turns. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following DC Motor requires 3 point starter? Series motor. Shunt, compound and series motor. Shunt motor. Shunt motor as well as compound motors. Series motor. Shunt, compound and series motor. Shunt motor. Shunt motor as well as compound motors. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following statements are correct ? Both 1 and 2. None of these The leakage reactance of the induction motor should be small. A small value of leakage reactance will increase the maximum power output of motor. Both 1 and 2. None of these The leakage reactance of the induction motor should be small. A small value of leakage reactance will increase the maximum power output of motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the magnetization characteristics of a dc generator : 1. It represents the variation of field flux with field current. 2. Variation of open-circuit terminal voltage with field current is independent of speed 3. It is non-linear from zero to rated field current 4. It helps to determine the critical field resistance at a given speed 5. It always starts from the origin Which of these statements are correct ? 3 and 5 1, 2 and 5 2, 3 and 4 1 and 4 3 and 5 1, 2 and 5 2, 3 and 4 1 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machine torque is proportional to which of the following? armature current(Ia) both A and B flux(φ) None of these armature current(Ia) both A and B flux(φ) None of these ANSWER DOWNLOAD EXAMIANS APP