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Re: resistance in an LRC circuit used to calculate time constant



Hi Antonio,
                  I was thinking the same thing in the shower last night:


> Original Poster: "Antonio Carlos M. de Queiroz" <acmq-at-compuland-dot-com.br> 
> 
> Tesla List wrote:
>  
> > Original Poster: "Malcolm Watts" <malcolm.watts-at-wnp.ac.nz>
> 
> > However, it is strictly true. The gap can be treated as a voltage
> > source and therefore be ignored (unless one gets very picky). The
> > reason is that gap conduction voltage is rather more constant over a
> > range of currents (consider a sinusoidal signal)  than the voltage
> > across a resistance would be.
> 
> Something strange... The gap obviously dissipates energy, and
> the voltage across it changes polarity at each semicycle. It is
> a nonlinear resistor, but it is a resistor. It can be replaced
> by an equivalent linear resistor that dissipates the same amount
> of energy. An interesting theoretical consideration is if a
> nonlinear resistor that keeps a constant voltage across it,
> only changing the polarity of the voltage in response to the
> current, changes the oscillation frequency of an LC circuit.

It must be dissipative of course. Maybe anti-parallel diodes in series 
with some real resistance of some kind?  One cannot ignore the 
obvious linear decrement.

Regards,
Malcolm