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In a series LCR circuit with an ac sourc...

In a series `LCR` circuit with an `ac` source of `50 V,R=300 Omega`,frequency `v=50/piHz`.The average electric field energy, stored in the capacitor and average magnetic energy stored in the coil are `25 mJ` and `5 mJ` respectively.The `RMS` current in the circuit is `0.10 A`.Then find

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To solve the problem step by step, we will follow the information provided in the question and the video transcript. ### Step 1: Calculate the capacitance (C) using the energy stored in the capacitor The average electric field energy stored in the capacitor is given by: \[ U_C = \frac{1}{2} C V_{rms}^2 \] Given \( U_C = 25 \, \text{mJ} = 25 \times 10^{-3} \, \text{J} \). Rearranging the formula to find \( C \): \[ C = \frac{2 U_C}{V_{rms}^2} \] We will need to calculate \( V_{rms} \) later, but we can express it in terms of \( I_{rms} \) and \( R \): \[ V_{rms} = I_{rms} \cdot R \] Given \( I_{rms} = 0.10 \, \text{A} \) and \( R = 300 \, \Omega \): \[ V_{rms} = 0.10 \times 300 = 30 \, \text{V} \] Now substituting \( V_{rms} \) back into the capacitance equation: \[ C = \frac{2 \times 25 \times 10^{-3}}{30^2} = \frac{50 \times 10^{-3}}{900} = \frac{50}{900} \times 10^{-3} = \frac{1}{18} \times 10^{-3} \approx 0.0556 \, \text{F} \approx 20 \, \mu\text{F} \] ### Step 2: Calculate the inductance (L) using the energy stored in the inductor The average magnetic energy stored in the inductor is given by: \[ U_L = \frac{1}{2} L I_{rms}^2 \] Given \( U_L = 5 \, \text{mJ} = 5 \times 10^{-3} \, \text{J} \): \[ L = \frac{2 U_L}{I_{rms}^2} \] Substituting the known values: \[ L = \frac{2 \times 5 \times 10^{-3}}{(0.10)^2} = \frac{10 \times 10^{-3}}{0.01} = 1 \, \text{H} \] ### Step 3: Calculate the voltage across the inductor (V_L) The voltage across the inductor is given by: \[ V_L = I_{rms} \cdot X_L \] Where \( X_L = \omega L \) and \( \omega = 2 \pi f \). Given \( f = \frac{50}{\pi} \): \[ \omega = 2 \pi \left(\frac{50}{\pi}\right) = 100 \, \text{rad/s} \] Thus, \[ X_L = 100 \cdot 1 = 100 \, \Omega \] Now substituting back to find \( V_L \): \[ V_L = 0.10 \cdot 100 = 10 \, \text{V} \] ### Step 4: Calculate the voltage across the capacitor (V_C) The voltage across the capacitor is given by: \[ V_C = I_{rms} \cdot X_C \] Where \( X_C = \frac{1}{\omega C} \): \[ X_C = \frac{1}{100 \cdot 20 \times 10^{-6}} = \frac{1}{0.002} = 500 \, \Omega \] Thus, \[ V_C = 0.10 \cdot 500 = 50 \, \text{V} \] ### Step 5: Calculate the total RMS voltage (V_rms) Using the formula for total voltage in an LCR circuit: \[ V_{rms} = \sqrt{V_R^2 + V_L^2 + V_C^2} \] Where \( V_R = 30 \, \text{V}, V_L = 10 \, \text{V}, V_C = 50 \, \text{V} \): \[ V_{rms} = \sqrt{30^2 + 10^2 + 50^2} = \sqrt{900 + 100 + 2500} = \sqrt{3500} \approx 59.16 \, \text{V} \] ### Final Answer The RMS voltage \( V_{rms} \) in the circuit is approximately \( 59.16 \, \text{V} \).

To solve the problem step by step, we will follow the information provided in the question and the video transcript. ### Step 1: Calculate the capacitance (C) using the energy stored in the capacitor The average electric field energy stored in the capacitor is given by: \[ U_C = \frac{1}{2} C V_{rms}^2 \] Given \( U_C = 25 \, \text{mJ} = 25 \times 10^{-3} \, \text{J} \). ...
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