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Similarly average value for sinusoidal voltage, V = 0.637 V m
av
Therefore, average value
Form factor
As the name suggests, form factor is an indicator of the shape or the form of
the ac wave. It is the ratio of the RMS value to the average value of an
alternating quantity. For a sinusoidal varying quantity, the form factor K is
f
The sharper the wave shape, the more will be the value of the form factor.
For example, for a triangular wave, form factor will be more than 1.11 and
for a rectangular wave form factor will be less than 1.11 (in fact, its value
will be 1). The peak or crest factor is the ratio of peak or maximum value to
its rms value.
It is obvious that by knowing the value of the form factor, the RMS value
can be calculated if the average or mean value is known.
3.1.7 RMS and Average Values of Half-wave-rectified Alternating Quantity
