Doubts about linear elements of electrical circuits

AI Thread Summary
The discussion centers on the definitions and relationships of impedance, admittance, reactance, and susceptance in electrical circuits. The first doubt involves the formulation of susceptance B, with two proposed equations differing only by sign, which is deemed irrelevant due to the complex nature of reactance. The second doubt questions the definitions of conductance G, highlighting a distinction between its general and specific forms, where the latter applies when reactance X equals zero. Participants note that conventions exist for the signs of reactance and suggest that similar conventions may apply to susceptance. Overall, the conversation seeks clarity on these electrical concepts and their interrelations.
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First doubt: The impedance Z is defined how Z = R + j X and the reactance X can be wrote how:

69fce93e83daf93f03b01dbcfbf47065.png


Source: https://en.wikipedia.org/wiki/Electrical_reactance

So, by analogy, the admitance Y is defined how Y = G + j B and the susceptance B can be wrote how what? So:
B = \left( \frac{\omega C}{1} - \frac{1}{\omega L} \right)
Or this form:
B = \left( \frac{1}{\omega L} - \frac{\omega C}{1} \right)
?

Help: https://it.wikipedia.org/wiki/SuscettanzaSecond doubt: in this page: "https://en.wikipedia.org/wiki/Electrical_resistance_and_conductance", the condutance G is defined how the reciprocal of R, BUT, BUT, in this page: "https://en.wikipedia.org/wiki/Susceptance", the condutance G is defined now how:
G = \left( \frac{R}{R^2+X^2} \right)
So, this last equation is the general definition of G and the first definition is the particular case, when X = 0, correct!?
 
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Hi,

About your first question, both forms differ only in the sign and since the reactance is a complex magnitude, the sign is not relevant.

As for your second question, I don't see in https://en.wikipedia.org/wiki/Susceptance the definition of G that you have written.Sergio
 
USeptim said:
Hi,

About your first question, both forms differ only in the sign and since the reactance is a complex magnitude, the sign is not relevant.

Exist a convention (maybe, can be that exist a good reason for this convention, but I don't know) for the signal of X, if X>0, thus the X is a indutive reactance and if X<0, thus X is capacitive reactance.

So, the duality of the capacitance is the elastance and the duality of the indutance is the relutance. So, by analogy, shoud exist a convention (or a deduction) for the signal of B too. What would be?
 
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