AC FUNDAMENTALS MCQs Part 1

1. The form factor in reference to alternating current wave form represents the ratio of
a. the average value to the R.M.S value
b. the peak value to the R.M.S values
c. the R.M.S value to the average value
d. the R.M.S value to the peak value

2. If the current and voltage are out of by 90 degree the power is
a. Minimum
b. Maximum
c. Zero
d. 1.1 V.I

3. The form factor of a 220 V , 50 Hz A.C waveform is
a. 1.5
b. 1.14
c. 1.11
d. 0.85

4. For the above wave the rms value will be
a. 1.1 A
b. 1.5 A
c. 1.528 A
d. 2 A

5. The average value of the above voltage is
a. ymax/2
b. ymax/3
c. 2/3 ymax
d. 3/2 ymax

6. The form factor will be
a. 1.0
b. 1.100
c. 1.11
d. 1.187

7. The peak factor of a wave is
a. maximum value / r.m.s value
b. maximum value / average value
c. average value / r.m.s value
d. r.m.s value / average value

8. In the above case the value of which parameter for full sine wave will be more?
a. form factor
b. peak factor
c. average value
d. none of the above

9. In the above case , the average value of the current will be
a. 5 A
b. 3.18 A
c. 1.57 A
d. 1.10 A

10. When the sole purpose of an alternating current is to produce heat, the selection of conductor is based on
a. peak value of current
b.average value of current
c. rms value of current
d. any of the above

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