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An L-C-R series circuit with L = 0.120 H...

An `L-C-R` series circuit with `L = 0.120 H, R = 240 a`, and `C = 7.30muF` carries an rms current of `0.450 A` with a frequency of `400 Hz`.
(a) What are the phase angle and power factor for this circuit?
(b) What is the impedance of the circuit?
(c) What is the rms voltage of the source?
(d) What average power is delivered by the source?
(e) What is the average rate at which electrical energy is converted to thermal energy in the resistor?
(f) What is the average rate at which electrical energy is dissipated ( converted to other forms) in the capacitor?
(g) In the inductor ?

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To solve the problem step by step, we will go through each part of the question systematically. ### Given Data: - Inductance, \( L = 0.120 \, \text{H} \) - Resistance, \( R = 240 \, \Omega \) - Capacitance, \( C = 7.30 \, \mu\text{F} = 7.30 \times 10^{-6} \, \text{F} \) - RMS Current, \( I_{\text{rms}} = 0.450 \, \text{A} \) - Frequency, \( f = 400 \, \text{Hz} \) ### (a) Phase Angle and Power Factor 1. **Calculate Inductive Reactance \( X_L \)**: \[ X_L = 2 \pi f L = 2 \pi (400) (0.120) = 301.59 \, \Omega \approx 301.6 \, \Omega \] 2. **Calculate Capacitive Reactance \( X_C \)**: \[ X_C = \frac{1}{2 \pi f C} = \frac{1}{2 \pi (400) (7.30 \times 10^{-6})} \approx 54.5 \, \Omega \] 3. **Calculate Phase Angle \( \phi \)**: \[ \tan \phi = \frac{X_L - X_C}{R} = \frac{301.6 - 54.5}{240} \approx 1.030 \] \[ \phi = \tan^{-1}(1.030) \approx 45.8^\circ \] 4. **Calculate Power Factor**: \[ \text{Power Factor} = \cos \phi = \cos(45.8^\circ) \approx 0.697 \] ### (b) Impedance of the Circuit 1. **Calculate Impedance \( Z \)**: \[ Z = \sqrt{R^2 + (X_L - X_C)^2} = \sqrt{240^2 + (301.6 - 54.5)^2} \] \[ Z = \sqrt{240^2 + 247.1^2} \approx 344 \, \Omega \] ### (c) RMS Voltage of the Source 1. **Calculate RMS Voltage \( V_{\text{rms}} \)**: \[ V_{\text{rms}} = I_{\text{rms}} \times Z = 0.450 \times 344 \approx 154.8 \, \text{V} \approx 155 \, \text{V} \] ### (d) Average Power Delivered by the Source 1. **Calculate Average Power \( P_{\text{avg}} \)**: \[ P_{\text{avg}} = V_{\text{rms}} \times I_{\text{rms}} \times \cos \phi \] \[ P_{\text{avg}} = 155 \times 0.450 \times 0.697 \approx 48.6 \, \text{W} \] ### (e) Average Rate of Thermal Energy Conversion in the Resistor 1. **Calculate Average Power in Resistor**: \[ P_R = I_{\text{rms}}^2 \times R = (0.450)^2 \times 240 \approx 48.6 \, \text{W} \] ### (f) Average Rate of Energy Dissipated in the Capacitor 1. **Average Power in Capacitor**: \[ P_C = 0 \, \text{W} \quad (\text{No power is consumed in the capacitor}) \] ### (g) Average Rate of Energy Dissipated in the Inductor 1. **Average Power in Inductor**: \[ P_L = 0 \, \text{W} \quad (\text{No power is consumed in the inductor}) \] ### Summary of Results: - (a) Phase Angle \( \phi \approx 45.8^\circ \), Power Factor \( \approx 0.697 \) - (b) Impedance \( Z \approx 344 \, \Omega \) - (c) RMS Voltage \( V_{\text{rms}} \approx 155 \, \text{V} \) - (d) Average Power \( P_{\text{avg}} \approx 48.6 \, \text{W} \) - (e) Power in Resistor \( P_R \approx 48.6 \, \text{W} \) - (f) Power in Capacitor \( P_C = 0 \, \text{W} \) - (g) Power in Inductor \( P_L = 0 \, \text{W} \)

To solve the problem step by step, we will go through each part of the question systematically. ### Given Data: - Inductance, \( L = 0.120 \, \text{H} \) - Resistance, \( R = 240 \, \Omega \) - Capacitance, \( C = 7.30 \, \mu\text{F} = 7.30 \times 10^{-6} \, \text{F} \) - RMS Current, \( I_{\text{rms}} = 0.450 \, \text{A} \) - Frequency, \( f = 400 \, \text{Hz} \) ...
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