[TowerTalk] two benefits of postings on Re: Resonance is

[Al Williams]

Some responses to my posting illustrate the benefit of multiple postings on 
the same subject but analyzed from a different point of view.

One point of view on resonance (actually reactance) was from the inductive 
or capacitive point of view.

The other point of view was from a phase shift point of view i.e. lagging 
current or leading current relative to the applied voltage.

Although both points of view have some benefit, I think that the phase shift 
view provides a better understanding e.g.

A single perfect (no resistance) inductor will have a reactance such that 
the current will lag the voltage. A single perfect capacitor will have a 
reactance such that the current will lead the voltage.

But what happens when the two are connected together when they have equal 
reactance values ignoring the phase shift?  Does the inductor reactance  and 
capacitor reactance somehow dissappear?  Or are the reactances still there 
but  the lagging current phase shift  is exactly offset by the leading 
current phase shift.

I would argue that virtually all circuits have both inductive and capacitive 
reactance (maybe extremely small L and C) at the same time  but they combine 
such that only one is dominant, thus inductive or capacitive. Maybe someone 
with more knowledge can correct me or explain it better.

To help reduce confusion the term impedance rather than reactance should be 
used when both reactances are included.

k7puc