Electrical Machines In a DC generator, if P be the number of poles and N be the rpm of the rotor, then frequency of magnetic reversals will be PN/60. PN/120. PN/3000. PN/2. PN/60. PN/120. PN/3000. PN/2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : Interpoles in dc machines 1. reducearmature reaction effects in the interpolar region 2. have the same dimension as main polls 3. have their windings connected in series with the armature 4. have same number of turns as the armature 5. have the polarity same as that of the main pole ahead in a motor From these, the correct statements are 1 and 3 1, 2, 3 and 5 1, 3 and 5 1, 2 and 3 1 and 3 1, 2, 3 and 5 1, 3 and 5 1, 2 and 3 ANSWER DOWNLOAD EXAMIANS APP
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. 0.443. 0.573. 0.512. 0.649. 0.443. 0.573. 0.512. 0.649. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a three phase star - delta transformer, what is the angle difference between primary and secondary phase voltages? Delta side lags by -30°. Star side leads by 30°. Star side lags by -30°. Delta side leads by 30°. Delta side lags by -30°. Star side leads by 30°. Star side lags by -30°. Delta side leads by 30°. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 1-phase induction motor, if the forward torque slip is S, what is the backward torque slip? 1/S 2-S S 1-S 1/S 2-S S 1-S ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which motors are preferred for refrigeration and air conditioning in smaller units? Stepper motors. Reluctance motors. Induction motors. Universal motors. Stepper motors. Reluctance motors. Induction motors. Universal motors. ANSWER DOWNLOAD EXAMIANS APP
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