An ac current changes direction
Rationalised 2023-24
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Alternating Current
with the source frequency and the attractive force would average to
zero Thus, the ac ampere must be defined in terms of some property
that is independent of the direction of the current Joule heating
is such a property, and there is one ampere of rms value of
alternating current in a circuit if the current produces the same
average heating effect as one ampere of dc current would produce
under the same conditions 5