In a series LCR circuit, $\mathrm{C}=2 \mu \mathrm{F}, \mathrm{L}=1 \mathrm{mH}$ and $\mathrm{R}=10 \Omega$.…

In a series LCR circuit, $\mathrm{C}=2 \mu \mathrm{F}, \mathrm{L}=1 \mathrm{mH}$ and $\mathrm{R}=10 \Omega$. The ratio of the energies stored in the inductor and the capacitor, when the maximum current flows in the circuit, is
  1. $5: 1$
  2. $3: 2$
  3. $1: 2$
  4. $1: 5$

Solution

In resonance condition (current is maximum), $\therefore \quad \mathrm{X}_{\mathrm{c}}=\mathrm{X}_{\mathrm{L}}$ $\therefore \quad$ The ratio of energies in the inductor and capacitor is: $\begin{aligned} & \frac{\mathrm{U}_{\mathrm{L}}}{\mathrm{U}_{\mathrm{C}}}=\frac{\mathrm{LI}^2}{\mathrm{CV}^2}=\frac{\mathrm{L}}{\mathrm{CR}^2} \quad \ldots\left(\because \frac{\mathrm{I}}{\mathrm{V}}=\frac{1}{\mathrm{R}}\right) \\ & \frac{\mathrm{U}_{\mathrm{L}}}{\mathrm{U}_{\mathrm{C}}}=\frac{10^{-3}}{2 \times 10^{-6} \times 10^2} \\ & \frac{\mathrm{U}_{\mathrm{L}}}{\mathrm{U}_{\mathrm{C}}}=\frac{5}{1} \end{aligned}$ /

Asked in: MHT CET 2023 (11 May Shift 2)

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