Why effective AC resistance is more than DC resistance of a
transmission line?

Answer Posted / mohd. kashan wali

AC resistance is greater than DC resistance.
The reason is:-

In AC, Skin effect occurs which means that current tends to flow through the skin of the wire than through the inner core,so net area of current flow in AC tends to reduce.
And Resistance is inverse proportional to Area, and as the net area of current flow decrease, so NET AC RESISTANCE INCREASES.
Now in DC current, there is uniform current flow.So net area of current flow through conductor is greater than AC,
THUS DC RESISTANCE IS LESS THAN AC

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