Easy MCQ +4 / -1 PYQ · JEE Mains 2024

In an a.c. circuit, voltage and current are given by:

$V=100 \sin (100 t) V$ and $I=100 \sin \left(100 t+\frac{\pi}{3}\right) \mathrm{mA}$ respectively.

The average power dissipated in one cycle is:

  1. A 5 W
  2. B 25 W
  3. C 2.5 W Correct answer
  4. D 10 W

Solution

<p>$$\begin{aligned} & P_{\text {avg }}=V_{\text {rms }} I_{r m s} \cos (\Delta \phi) \\ & =\frac{100}{\sqrt{2}} \times \frac{100 \times 10^{-3}}{\sqrt{2}} \times \cos \left(\frac{\pi}{3}\right) \\ & =\frac{10^4}{2} \times \frac{1}{2} \times 10^{-3} \\ & =\frac{10}{4}=2.5 \mathrm{~W} \end{aligned}$$</p>

About this question

Subject: Physics · Chapter: Alternating Current · Topic: AC Circuits: R, L, C

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