I have somehow worked myself into a mental loop that I need a push to break out of.(adsbygoogle = window.adsbygoogle || []).push({});

Consider an inductor in series with a resistor. In sinusoidal steady state, the combination has an impedance Z = R + jωL. The admittance is given by (1/Z) = (R-jωL)/(R^{2}+(ωL)^{2}), and if R is zero, it is simply -j/(ωL) as expected. But the admittance can be broken into conductance and suseptance, so the calculated admittance Y = G+jB = 0 - j/(ωL).

But I was expecting G = infinity!

Clearly I am confusing exactly how and when these quantities are defined. Any help would be appreciated.

-John

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# Impedance and Admittance

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