How to Calculate Impedance in an AC Circuit with Series Components?

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Homework Help Overview

The problem involves calculating the impedance in an AC circuit consisting of a resistor, inductor, and capacitor connected in series. The circuit is powered by a 90-V (rms) AC source at a frequency of 500 Hz.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to understand how to calculate the impedance and expresses uncertainty about starting the problem. Some participants provide equations for inductive and capacitive reactance, while others clarify the distinction between reactance and impedance.

Discussion Status

Participants are exploring different aspects of impedance calculation, with some providing equations and clarifications. There is an ongoing exchange of ideas, but no consensus has been reached regarding the approach to solving the problem.

Contextual Notes

The original poster has not provided specific details on prior knowledge or constraints related to homework rules, which may influence the discussion.

9.8m*s^-2
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Homework Statement



A 25-Ω resistance is connected in series with a 30-mH inductance and a 12-µF capacitor and are connected to a 90-V (rms) ac. If the frequency of the ac source is 500 Hz, calculate

(i) the current in the circuit.
(ii) the voltage across each element
(iii) the phase angle
(iv) the power dissipated in the circuit



Homework Equations





The Attempt at a Solution



I believe I have to begin this problem by calculating the impedance but I do not understand how to begin doing that.

Thank you.
 
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X_L=\omega L
X_C=\frac{1}{\omega C}
Z= R + i(X_L - X_C)
 
Well Impedence for each element is given by the equations that xcvxcvvc gave except with one little adjustment:

Z_L=j\omega L
Z_C=\frac{1}{j\omega C}
(The ones he gave were reactance)

\omega is the angular frequency which can be calculated by setting it equal to 2\pi f

From there you can solve the circuit.
 
Also, just in case you don't see it:
j = \sqrt{-1}
\frac{1}{j}= \frac{j}{j}\frac{1}{j} =\frac{j}{-1}=-j

which is why that capacitive reactance is subtracted when forming the expression for impedance.
 

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