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Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

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Denis McMahon <denismfmcmahon@gmail.com> wrote on 30 jan 2014 in 
comp.lang.javascript:

> On Thu, 30 Jan 2014 11:10:18 +0100, Evertjan. wrote:
> 
>> Impedance is the same, be it that the value is not linear for
>> alternating current, but depends on the frequency, so Ohm's law only
>> appies with a fixed frequency.
>
> Speaking as an electrical engineer by training, ohms law holds true for 
> all frequencies when considering impedance.

Speaking aas someone that likes to discuss by argument, not by anyone's 
status, I would say that wile true in mathemetical effect, it still is 
nonsense.

Ohm's law gives just the linear part of the equasion,
while impedance is the non-linear part governed 
by the pure capacitor and coil like parts.

That is the part where energy cannot be dissipated as heat energy,
it can only be electromagneticly be transmitted to elsewhere.

While the impedance of a lossy transmission cable of near infinite length
can nicely be used as a resistive load, and can be given a value in Ohms, 
that is just a mathematical limit making it look like a pure resistance for 
the frequency band it applies to, not for a direct current.

> As the impedance varies with frequency, so the relationship between 
> current and voltage varies in accordance with Ohms law such that at any 
> frequency, voltage (rms or peak) = current (rms or peak) * impedance.

Indeed, but that is not Ohm's law, 
it is only a formula looking like Ohms' law.

Ohm's law expects dissipation. 

> You also get a phase shift depending on the nature of the impedance 
> (capacitative or reactive) unless the impedance is a pure resistance.

The latter souds fishy to me. 
A pure resistance is just that, a resistance.
An impedance is not the non-resistive part of the load.

Yes, I know we sometimes call them impedance together,
but strictly speaking that is not correct.

Yes, I know that you can match a required and frequency dependent load 
impedance to a pure resistic, so frequency independent, load, but that does 
not mean they are the same. 

> A single set of v/i/z values 

Eh? This to do with lawn tennis?

> may only apply to a given frequency, but I 
> have to correct you as the statement that "Ohm's law only applies with a 
> fixed frequency" is incorrect. 

I did not say that, so why correct me?

Indeed that is incorrect.

Ohm's law only applies to a pure resistance,
so that must apply to all frequencies where such element is pure.

> Ohm's law always applies regardless of the frequency or combination
> of frequencies and rate(s) of change of those frequencies involved.

Ohm's law always applies, but only to pure resistances, 
or more practical, the pure resistive part of the load.

a = b x c applies to much more, 
like when buying apples, 
but that is just the formula not the law.

-- 
Evertjan.
The Netherlands.
(Please change the x'es to dots in my emailaddress)

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Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-01-26 02:37 -0800
  Re: JavaScript unfairly blamed? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-01-26 11:52 +0100
    Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-01-26 12:04 -0800
      Re: JavaScript unfairly blamed? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-01-26 22:24 +0100
        Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-01-26 14:49 -0800
          Re: JavaScript unfairly blamed? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-01-27 02:14 +0100
            Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-01-27 18:30 -0800
              Re: JavaScript unfairly blamed? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-01-28 19:08 +0100
                Re: JavaScript unfairly blamed? Christoph Michael Becker <cmbecker69@arcor.de> - 2014-01-28 19:50 +0100
                Re: JavaScript unfairly blamed? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-01-28 21:18 +0100
                Re: JavaScript unfairly blamed? Christoph Michael Becker <cmbecker69@arcor.de> - 2014-01-28 22:27 +0100
                Re: JavaScript unfairly blamed? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-01-28 23:23 +0100
                Re: JavaScript unfairly blamed? Christoph Michael Becker <cmbecker69@arcor.de> - 2014-01-29 17:12 +0100
                Re: JavaScript unfairly blamed? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-01-31 22:30 +0100
                Re: JavaScript unfairly blamed? Christoph Michael Becker <cmbecker69@arcor.de> - 2014-02-01 22:35 +0100
                Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-01-28 19:59 -0800
                Re: JavaScript unfairly blamed? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-01-31 14:08 +0100
                Re: JavaScript unfairly blamed? Christoph Michael Becker <cmbecker69@arcor.de> - 2014-02-01 22:52 +0100
                Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-02-02 10:09 -0800
                Re: JavaScript unfairly blamed? Christoph Michael Becker <cmbecker69@arcor.de> - 2014-02-04 23:42 +0100
                Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-01-28 19:40 -0800
                Re: JavaScript unfairly blamed? Christoph Michael Becker <cmbecker69@arcor.de> - 2014-01-29 17:17 +0100
                Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-01-29 16:51 -0800
                Re: JavaScript unfairly blamed? Christoph Michael Becker <cmbecker69@arcor.de> - 2014-01-31 01:06 +0100
                Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-01-28 19:36 -0800
                Re: JavaScript unfairly blamed? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-01-31 14:47 +0100
      Re: JavaScript unfairly blamed? John Harris <niam@jghnorth.org.uk.invalid> - 2014-01-27 14:36 +0000
        Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-01-27 16:05 -0800
          Re: JavaScript unfairly blamed? John Harris <niam@jghnorth.org.uk.invalid> - 2014-01-29 15:26 +0000
            Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-01-29 16:44 -0800
              "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-01-30 11:10 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? Tim Streater <timstreater@greenbee.net> - 2014-01-30 10:38 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-01-30 13:30 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? Denis McMahon <denismfmcmahon@gmail.com> - 2014-01-30 12:45 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-01-30 14:05 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? Dr J R Stockton <reply1400@merlyn.demon.co.uk.invalid> - 2014-01-31 21:32 +0000
                OT: "impedance mismatch" (was: "impedance mismatch", was: Re: JavaScript unfairly blamed?) Christoph Michael Becker <cmbecker69@arcor.de> - 2014-02-01 01:15 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? Denis McMahon <denismfmcmahon@gmail.com> - 2014-02-01 02:40 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-02-01 10:02 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-02-01 09:54 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? Denis McMahon <denismfmcmahon@gmail.com> - 2014-01-30 11:06 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-01-30 14:02 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "ViLco" <villiber@tin.it> - 2014-01-30 16:24 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? Denis McMahon <denismfmcmahon@gmail.com> - 2014-01-31 00:35 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-01-31 11:16 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-01-30 15:14 -0800
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-01-31 00:56 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2014-01-30 22:13 -0800
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-01-31 11:51 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? Dr J R Stockton <J.R.Stockton@physics.org> - 2014-01-31 19:58 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-02-01 09:30 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? Dr J R Stockton <reply1400@merlyn.demon.co.uk.invalid> - 2014-02-02 17:44 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-02-03 01:15 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? John Harris <niam@jghnorth.org.uk.invalid> - 2014-02-03 14:58 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? Tim Streater <timstreater@greenbee.net> - 2014-02-03 15:36 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-02-03 17:59 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? Tim Streater <timstreater@greenbee.net> - 2014-02-03 17:18 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-02-03 19:47 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? John Harris <niam@jghnorth.org.uk.invalid> - 2014-02-04 10:33 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-02-06 13:40 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? Dr J R Stockton <reply1400@merlyn.demon.co.uk.invalid> - 2014-02-06 10:12 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-02-07 10:32 +0100
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? Dr J R Stockton <reply1400@merlyn.demon.co.uk.invalid> - 2014-02-08 23:06 +0000
                Re: "impedance mismatch", was: Re: JavaScript unfairly blamed? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-02-09 10:33 +0100

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