Answer / prashant sharma

power factor is simply the angle(phase) diffrence b/w the
voltage and current wave in a system.
in case of d.c. voltage, as it is not a fluctuating wave,
the resulting current is also non fluctuating. thus no
phase angle exists b/w them.

Answer / jain c

power factor is the cosine of angle between voltage and
current. In case of DC the angle between voltage and
current is zero. therefore power factor always remains 1.

power factor= cos(angle between vtg and current)
here angle = zero
therefore power factor = 1

Answer / s.rajasekar

dc is the directcurrent it has no phase difference between
the voltage and current is unity or zero.so we won't
consider about PF

Answer / abhi...

In dc there is no phase difference between current& voltage
(is zero) so.........
power factor= cos(angle between vtg and current)
here angle = zero
therefore power factor = 1

Answer / syed vikhar ahmad

as we know power factor is the cosine of the angle between
voltage and current and in dc there is 0 angle between
voltage and current so the power factor is always one thats
why we dont discuss power factor in dc.

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