Phasor algebra in AC circuit analysis

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SUMMARY

The discussion centers on solving an AC circuit problem using phasor algebra, specifically for an L-C-R circuit with a peak voltage of ##V_0## and angular frequency ##\omega_0##. The user derived the current through the circuit using phasor diagrams and equations, ultimately questioning the accuracy of the book's provided answer and their own understanding of phasor algebra. The consensus is that the user has applied phasor algebra correctly, and the discrepancy in the answer is likely due to a printing error in the textbook.

PREREQUISITES
  • Understanding of phasor diagrams in AC circuit analysis
  • Knowledge of L-C-R circuit components and their behavior
  • Familiarity with complex impedance and its calculation
  • Basic proficiency in vector algebra and calculus
NEXT STEPS
  • Study phasor algebra in-depth to enhance AC circuit analysis skills
  • Review complex impedance calculations in L-C-R circuits
  • Explore resources such as "Fundamentals of Electric Circuits" for practical applications
  • Practice solving AC circuit problems using phasor diagrams and equations
USEFUL FOR

Students and professionals in electrical engineering, particularly those focusing on AC circuit analysis and phasor algebra applications.

Titan97
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Homework Statement


Find the peak value of current through the AC source of the following L-C-R circuit, if peak voltage is ##V_0## and angular frequency is ##\omega_0##.
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Homework Equations


I have learned Vector algebra and calculus (single variable). I was taught how to use phasor diagrams for AC circuits. (only the basics).
From my book:

The Attempt at a Solution


$$i_R=\frac{V_0}{R}\sin\omega t$$
$$i_C=V_0\omega C\cos\omega t$$
$$i_L=-\frac{V_0}{\omega L}\cos \omega t$$
$$i=\frac{V_0}{R}\sin\omega t+V_0\big(\omega C-\frac{1}{\omega L}\big)\omega C\cos\omega t$$

If current is taken along positive ##X##-axis, then $$i=\frac{V_0}{Z}=\frac{V_0}{R}+V_0\big(\omega C-\frac{1}{\omega L}\big)j$$

$$\vert Z\vert=\frac{1}{\sqrt{\frac{1}{R^2}+\big(\omega C-\frac{1}{\omega L}\big)^2}}$$

$$i_0=\frac{V_0}{Z}=V_0\sqrt{\frac{1}{R^2}+\big(\omega C-\frac{1}{\omega L}\big)^2}$$

These are the problems I face:
1. The answer given is: $$V_0\big({\frac{1}{R^2}+\big(\omega C-\frac{1}{\omega L}\big)^2}\big)^2$$
(probably a printing error)

2. I applied phasor algebra blindly. Hence, I am not sure if I solved it properly.

3. So should I learn phasor algebra? Can you suggest a book for learning it (or a webpage)?
 
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I believe you have solved it correctly! There's definitely a printing mistake in the answer given in the book. If you've done this problem by yourself, then I think you have a proper understanding of phasor algebra.
 

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