Circuit analysis complex numbers

AI Thread Summary
The discussion revolves around a circuit analysis problem involving complex numbers, specifically the calculations of impedances for capacitors, inductors, and resistors. The user expresses frustration over repeatedly arriving at the same answer despite extensive review of the textbook. Key calculations include the impedance of a capacitor and inductor, leading to the combined impedance of a circuit segment. A critical point highlighted is the importance of converting frequency from Hz to rad/sec to avoid errors. Ultimately, the user realizes a simple mistake in their calculations, leading to a resolution of their confusion.
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Homework Statement


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I'm going crazy. I've done this problem nearly 20 times and keep getting the same answer. I've read my textbook so many times too! What am I doing wrong?

Homework Equations


Zcapacitor = 1/(jwC)
Zinductor = jwL
Zresistor = R

The Attempt at a Solution



Z for the capacitor -j1.667*10^3
Z for the inductor is j0.6

Z1 contains the capacitor and resistor on the righthand side of the circuit

Z1 = 2 - j1.667*10^3

Calculate Z12 (Z1 in parallel with the 22 ohm resistor)

1/Z12 = 1/22 + (2+j1.667*10^3)/(2.78*10^6)
Z12 =21.99-j2.903*10^-1

Z123 = Z12 in series with the inductor = 21.99 - j0.2903 + j0.6 = 21.99 + j0.309
 
Physics news on Phys.org
Don't forget to convert simple frequency f, which has units of Hz, to radial frequency ω, which has units of rad/sec.
 
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collinsmark said:
Don't forget to convert simple frequency f, which has units of Hz, to radial frequency ω, which has units of rad/sec.

Such a simple mistake on my part. Thanks.
 

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