In each of the three coils of a three phase generator, an alternating voltage having an r.m.s. value of 220 V is induced. Which of the following values is indicated by the voltmeters ______?

Related Mcqs:

1. What will be the phase angle between two alternating waves of equal frequency, when one wave attains maximum value the other is at zero value________ ?

   A. 0°
   B. 45°
   C. 90°
   D. 180°

2. The r.m.s. value of alternating current is given by steady (D.C.) current which when flowing through a given circuit for a given time produces__________?

   A. the more heat than produced by A.C. when flowing through the same circuit
   B. the same heat as produced by A.C. when flowing through the same circuit
   C. the less heat than produced by A.C. flowing through the same circuit
   D. none of the above

3. In the case of an unsymmetrical alternating current the average value must always be taken over__________?

   A. unsymmetrical part of the wave form
   B. the quarter cycle
   C. the half cycle
   D. the whole cycle

4. The reactance offered by a capacitor to alternating current of frequency 50 Hz is 20 Q. If frequency is increased to 100 Hz, reactance becomes_______ohms?

   A. 2.5
   B. 5
   C. 10
   D. 15

5. The frequency of an alternating current is____________?

   A. the speed with which the alternator runs
   B. the number of cycles generated in one minute
   C. the number of waves passing through a point in one second
   D. the number of electrons passing through a point in one second

6. When an alternating current passes through an ohmic resistance the electrical power converted into heat is__________?

   A. apparent power
   B. true power
   C. reactive power
   D. none of the above

7. The power consumed in a circuit element will be least when the phase difference between the current and voltage is__________?

   A. 180″
   B. 90°
   C. 60°
   D. 0°

8. The phase difference between voltage and current wave through a circuit element is given as 30°. The essential condition is that

   A. both waves must have same frequency
   B. both waves must have identical peak values
   C. both waves must have zero value at the same time
   D. none of the above

9. The power consumed in a circuit element will be least when the phase difference between the current and voltage is________?

   A. 180″
   B. 90°
   C. 60°
   D. 0°

10. The product of apparent power and cosine of the phase angle between circuit voltage and current is

    A. true power
    B. reactive power
    C. volt-amperes
    D. instantaneous power