Question 260: AC fundamentals

Question

In series LCR circuit R $=18 \Omega$ and impedance is $30 \Omega$. An rms voltage 210 V is applied across the circuit. The true power consumed in AC circuit is nearly

Accepted Answer

$$ \begin{aligned} & \mathrm{P}=\mathrm{e}_{\mathrm{rms}} \mathrm{I}_{\mathrm{rms}} \cos \phi \ & 	ext { But, } \cos \phi=\frac{\mathrm{R}}{\mathrm{Z}} 	ext { and } \mathrm{e}_{\mathrm{rms}}=\mathrm{I}_{\mathrm{rms}} 	imes \mathrm{Z} \ & \mathrm{P}=\mathrm{e}_{\mathrm{rms}} 	imes \frac{\mathrm{e}_{\mathrm{rms}}}{\mathrm{Z}} 	imes \frac{\mathrm{R}}{\mathrm{Z}}=\frac{210 	imes 210 	imes 18}{30 	imes 30} \ &=882 \mathrm{~W} \end{aligned} $$

Answer

210 W

Answer

400 W

Answer

800 W

Answer

900 W

AC fundamentals

In series LCR circuit R =18 \Omega and impedance is 30 \Omega. An rms voltage 210 V is applied across the circuit. The true power consumed in AC circuit is nearly

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