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The current through a resistor in an a.c circuit is given...

The current through a resistor in an a.c circuit is given as 2 sin wt. Determine the d.c. equivalent of the current

A.

A/√2

B.

2/√A

C.

2 A

D.

√2 A

Correct answer is B

If I = 2 Sin wt; but in a.c. circuit current I = I0 Sin wt; thus comparing the two equations, it implies that I0 = 2A; Again, the root means square (I(rms)) of an a.c. current is the value of the d.c. current that will dissipate the same amount of heat in a given resistance as the a.c.
and I(rms) = I0/√2 = 2.0A/√2