Working out the impedance of a network query

AI Thread Summary
The discussion focuses on calculating the J notation impedance of a network consisting of an inductor in series with a resistor, both in parallel with a capacitor. The user proposes using the product-over-sum formula for the inductor and capacitor and applies complex conjugates to simplify the expression. They seek confirmation on their approach, specifically regarding the manipulation of the impedance formula. A participant confirms that the user's method appears correct. The conversation emphasizes the importance of understanding complex impedance in electrical networks.
lubo
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Homework Statement



Calculate the J notation impedance of the network

We have an inductor in series with a resistor and both in parallel with a capacitor.


Homework Equations





The Attempt at a Solution


i believe it is true that if I was to say: if I have an inductor in parallel with a capacitor then:

Product/Sum = XL*-XC/XL-XC

This would then go like (XL*-XC)(XL+XC) / (XL-XC)(XL+XC) because of complex conjugate.

If this then was as above in the original setup:

We have an inductor in series with a resistor and both in parallel with a capacitor.

then could you say:

(R+JXL)*(-JXC) / (R+JXL-JXC) or (R+J(XL-XC))

Could I then say by complex conjugate:

((R+JXL)*(-JXC)) (R-J(XL-XC)) / (R+J(XL-XC)) (R-J(XL-XC))

Thanks for any help in advance, it is much appreciated.
 
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lubo said:
We have an inductor in series with a resistor and both in parallel with a capacitor.

then could you say:

(R+JXL)*(-JXC) / (R+JXL-JXC) or (R+J(XL-XC))

Could I then say by complex conjugate:

((R+JXL)*(-JXC)) (R-J(XL-XC)) / (R+J(XL-XC)) (R-J(XL-XC))

It looks correct.


ehild
 
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