Find the impedance and ω for (R and L in series, & C in || )

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The discussion focuses on finding the impedance (Z) of a circuit with a resistor (R) and inductor (L) in series, and a capacitor (C) in parallel. To determine resonance, Z must be expressed in terms of real numbers, leading to the condition where the imaginary part equals zero. The user correctly identifies the series impedance of R and L as R + iωL and seeks to combine this with the impedance of the capacitor. Clarifications are provided regarding the notation for imaginary numbers in electrical analysis, emphasizing the use of 'j' instead of 'i'. The conversation confirms the approach to solving for Z and ω is on the right track.
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Homework Statement


Find the impedance (Z) of the circuit in the shown figure (R and L in series, and C in parallel with them). A circuit is said to be in resonance if Z is real, find ω in terms of R, L, and C?
upload_2016-10-2_12-56-13.png


Homework Equations


VR= RIeiωt
VL= LiωIeiωt
VC= (Ieiωt)/(iωc)

What I mean by I is I (not) H didn't know how to write it and i imaginary number, I hope the I wrote the equations clearly.

The Attempt at a Solution


What I think about is:
1. Find Z.
2. Put Z in term of x+iy.
3. If Z is real then y=0.
4. find ω from y=0.

If that correct I should find Z, but I'm not sure about it.
first I found Zseries for R & L = R+iωL
then Z = Zseries || ZC
Am I right? or there are some specific formulas as if all R, L & C are in series?
 
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notnerd said:
first I found Zseries for R & L = R+iωL
then Z = Zseries || ZC
Am I right?
Yes.
notnerd said:
2. Put Z in term of x+iy.
3. If Z is real then y=0.
4. find ω from y=0.
Right.
 
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notnerd said:
What I mean by I is I (not) H didn't know how to write it and i imaginary number, I hope the I wrote the equations clearly.
To avoid confusion with current, imaginary number 'i' in mathematics is denoted by 'j' in electrical circuit analysis. So the reactances become jXL and -jXc (Note 1/j= -j).
 
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