PHYSICS

JAMB 2001 - Question 40

Physics 2001 JAMB Past Questions - Question 40: The current through a resistor in an a.c. circuit is given as 2 sin Determine the d.c. equivalent of the current.

Choose the correct answers from the options given.
The current through a resistor in an a.c. circuit is given as 2 sin Determine the d.c. equivalent of the current.
A:
B:
C:
D:
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Correct Answer

E

Explanation

Ir.m.s=1P/^2 =2/^2=^2In an AC circuit, the current is typically represented as a sinusoidal function of time. The equation you provided is 2sin(ωt), where ω represents the angular frequency and t is time.

To find the DC (direct current) equivalent of this AC current, you need to find the average or mean value of the current over one complete cycle. In this case, the AC current is a sinusoidal waveform, and its DC equivalent is the average value of this waveform.

The average value of a sine wave over one complete cycle is zero. This is because the positive and negative halves of the sine wave cancel each other out when you integrate it over a full cycle.

So, the DC equivalent of the given AC current, 2sin(ωt), is 0. In other words, the average value of this AC current over one cycle is zero, and there is no constant DC component.