(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Vs=7200V 0 degrees

ZLine=2Ω+20jΩ

ZLoad=138Ω+460jΩ

XC=unknown capacitance

(omega not given)

Find the capacitive reactance when, place in parallel with ZLoad will make the load appear purely resistive

2. Relevant equations

conj(Zline) =2Ω-20jΩ (for max power transfer to the load)

Zparallel=[(Zload)(XC)]/[Zload+XC] =Zline

3. The attempt at a solution

I multiply the numberator and denomator by the conjugate of (138+j460-jXC) to get

[[(460XC-j138XC)*(138-i(460-XC)]/(138^2+(460-XC)^2)]=2-20j

when I rearrange, I end up with:

68XC^2+240XC^2-9800XCj+980XC+210447i=230644

as you can see, I end up with a complex number as a solution, which does not make sense

How should I approach these kinds of problems where the transfer function (sans a component value) and the resulting vector is known?

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# Homework Help: Transfer function and magintude known, unsure how to appoarch

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