What is difference between AC and DC resistance
Answer Posted / engineering.force
the dc resistance remains constant provided the external
conditions like temperature, moisture, pressure etc. do not
change. the dc resistance does not have any relation
whatsoever to the frequency as there is no frequency for the
dc supply. the current flows uniformly through the cable and
for most cases, the current density at all points is the same.
the ac resistance is frequency dependent. it do not remain
constant with variation in frequency. the self inductance
and mutual inductance of the transmission line play a role
in defining the ac resistance of the transmission line. if
frequency is increased, the resistance of the core of cable
will increase. the current density is not uniform at all
points in the conductor. also, the effective surface area of
the conductor will reduce with increase in the frequency.
this is called skin effect.
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