Phasor algebra in AC circuit analysis

AI Thread Summary
The discussion focuses on finding the peak current in an L-C-R circuit using phasor algebra. The user presents their calculations for current through resistors, capacitors, and inductors, ultimately deriving the total current equation. They express uncertainty about their method and suspect a printing error in the provided answer from their textbook. Participants confirm that the user's approach appears correct and suggest that further study of phasor algebra would be beneficial. The conversation emphasizes the importance of mastering phasor techniques for accurate AC circuit analysis.
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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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