Question 287: AC fundamentals

Question

In LCR series circuit, R = 18 $\Omega$ and impedance $33 \Omega$. An r.m.s. voltage of 220 V is applied across the circuit. The true power consumed in a.c. circuit is

Accepted Answer

Given:
Resistance, $R = 18\,\Omega$
Impedance, $Z = 33\,\Omega$
Applied RMS voltage, $V_{	ext{rms}} = 220\,	ext{V}$
Step 1: Calculate the RMS current ($I_{	ext{rms}}$):
$ I_{	ext{rms}} = \frac{V_{	ext{rms}}}{Z} = \frac{220}{33} = 6.67\,	ext{A} $
Step 2: Calculate true power consumed ($P$):
True power consumed in the circuit (also called average power) is given by
$ P = I_{	ext{rms}}^2 R $
$ P = (6.67)^2 	imes 18 = 44.44 	imes 18 = 800\,	ext{W} $
Correct answer: Option C, 800 W

Answer

400 W

Answer

600 W

Answer

800 W

Answer

900 W

AC fundamentals

In LCR series circuit, R = 18 \Omega and impedance 33 \Omega. An r.m.s. voltage of 220 V is applied across the circuit. The true power consumed in a.c. circuit is

Choose the correct answer: