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Re: JavaScript unfairly blamed?

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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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#22883 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

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.

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.

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

A single set of v/i/z values 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. Ohm's law always applies regardless of the 
frequency or combination of frequencies and rate(s) of change of those 
frequencies involved.

-- 
Denis McMahon, denismfmcmahon@gmail.com

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#22886 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

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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#22888 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

Evertjan. wrote:

>> 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?

ROTFL
-- 
"Un pasto senza vino e' come un giorno senza sole"
Anthelme Brillat Savarin 

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#22898 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

On Thu, 30 Jan 2014 14:02:51 +0100, Evertjan. wrote:

> 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.
>> 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.

I was obviously unclear. Impedance normally has a capacitive or inductive 
component, also referred to as the reactive part, as well as the purely 
resistive part. Impedance is the vector sum of reactance and resistance, 
where reactance is at a phase angle of either +90 or -90, depending on 
whether you consider v to i or i to v, and whether it is capacitive 
reactance or inductive reactance.

> 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.

Indeed, as soon as AC is involved, frequency becomes part of the equation 
that you can not ignore.

>> A single set of v/i/z values
> 
> Eh? This to do with lawn tennis?

voltage / current / impedance

>> 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?

You said: "Ohm's law only appies with a fixed frequency". It is the last 
phrase of the first quoted paragraph of yours above. I added what I 
perceived to be a missing l to change "appies" into "applies".

-- 
Denis McMahon, denismfmcmahon@gmail.com

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#22902 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

Denis McMahon <denismfmcmahon@gmail.com> wrote on 31 jan 2014 in 
comp.lang.javascript:

> You said: "Ohm's law only appies with a fixed frequency".

Sorry, I did not mean that. [perhaps I was thinking of "apples". ;-) ]

I did mean that the formula of Ohm's law only applies here with a fixed 
frequency, but not Ohm's law itself, as this only applies to pure resistive 
loads.

In practice there are no "pure" resistive loads, seen against frequency:

Buy a quality resistor, above a certain frequency things like skin-effect, 
capacitor and inductor effects, will take their toll and add nonresistive 
properties to the component.

> It is the last 
> phrase of the first quoted paragraph of yours above. I added what I 
> perceived to be a missing l to change "appies" into "applies".

see above ;-)

"pure apples", meaning "no pears"?  

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

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#22895 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

On Thursday, January 30, 2014 4:10:18 AM UTC-6, Evertjan. wrote:
> [...]
> btw, the resistance of water though a tube, when the flow is low and so 
> laminal, follows Ohm's law by having a fixed resistance; 
[...]

Do you have any references for further reading on this topic?

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#22896 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

"Michael Haufe (TNO)" <tno@thenewobjective.com> wrote on 31 jan 2014 in 
comp.lang.javascript:

> On Thursday, January 30, 2014 4:10:18 AM UTC-6, Evertjan. wrote:
>> [...]
>> btw, the resistance of water though a tube, when the flow is low and so 
>> laminal, follows Ohm's law by having a fixed resistance;

laminar, sorry.
 
> [...]
> 
> Do you have any references for further reading on this topic?

You only need to have Google as your friend.

Any reasonabley good doctor who uses a stethoscope should know the 
underlying principles by heart. 

Looking for "laminar flow" + "turbulent flow" [+ "cardiovascular"]:

<http://www.cvphysiology.com/Hemodynamics/H007.htm>
<https://www.inkling.com/read/cardiovascular-physiology-pappano-wier-
10th/chapter-6/flow-may-be-laminar-or-turbulent>
<http://answers.yahoo.com/question/index?qid=20090327065322AAvDLrz>

Some pathological heart murmurs only are important for their diagnostic 
value in congenital adnormalities and acquired cardiovascular disease, other 
murmurs, depending on the timing in the heart cycle and lenthe and other 
qualirues, especially the ones sounding high pitched, are typical for 
turbulences that locally destroy the endothelium, the inner lining of the 
haert, or of its valves, and make trombus and bacterial growth possible.

<http://en.wikipedia.org/wiki/Laminar_flow>
<http://en.wikipedia.org/wiki/Turbulence>
<http://en.wikipedia.org/wiki/Reynolds_number>
<http://medical-dictionary.thefreedictionary.com/Reynold's+number>
<http://www.engineeringtoolbox.com/reynolds-number-d_237.html>

<http://www.scai.org/SecondsCount/Disease/CongenitalHeartDiseases.aspx>
<http://www.scai.org/SecondsCount/Disease/AcquiredHeartDiseaseinChildren.asp
x>

Is this enough for starters?


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

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#22899 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

On Thursday, January 30, 2014 5:56:09 PM UTC-6, Evertjan. wrote:

[...]

> Is this enough for starters?

Indeed. I've just never seen Ohm's law outside the context of electricity.

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#22903 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

"Michael Haufe (TNO)" <tno@thenewobjective.com> wrote on 31 jan 2014 in 
comp.lang.javascript:

> On Thursday, January 30, 2014 5:56:09 PM UTC-6, Evertjan. wrote:
> 
> [...]
> 
>> Is this enough for starters?
> 
> Indeed. I've just never seen Ohm's law outside the context of electricity.

Everywhere where there pressure/tension, current/flow and resistance,
as well as energy loss, pressure/tension change and current/flow, 
we see the shades of Ohm's law. 

Even in road traffic movement, where there is a strong additional not pure 
resistive condition called collective emotion.

Ohm's law itself applies only to the pure resistive component, but is a 
great help in visualizing what happens in the real world.

Viscosity, laminar flow friction, turbulent friction, gravity gradient,
surface tension effects, effects of temperature change by energy dissipation 
on the local viscosity, all have their effects on flow though a rigid or non 
rigid [vene] tube.

Turbulence not only originates in tube inner-lining irregularities, but also 
in tube bends and changes in diameter, etc. 

In sickle cell disease, the red blood cells change form due to a 
cristalising effect on the haemoglobin when [among other] the oxygen content 
drops, giving a dramatic local effect on the blood viscosity, [even an 
individual cell can get stuck in a capilary vene, blocking that vene and so 
generating infinite viscosity], and thereby lowering the oxygen even more. 

So even viscosity is not a constant in an single example.

Perhaps we should leave "Ohm alone" here, and develop formulas based on the 
idea that all energy must be preserved, using Javascript as a scripting 
tool.

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

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#22918 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

In comp.lang.javascript message <XnsA2C571A54D08Beejj99@194.109.133.133>
, Thu, 30 Jan 2014 11:10:18, Evertjan. <exxjxw.hannivoort@inter.nl.net>
posted:

>btw, the resistance of water though a tube, when the flow is low and so
>laminal, follows Ohm's law by having a fixed resistance;

Not true.  The flow is proportional to the pressure difference at low
flow rated, but what you describe is not the law of Georg Simon Ohm.  It
is more nearly a simplified case of Darcy's law; the Hagen–Poiseuille
equation applies.  Ohm's Law is specifically electrical.

-- 
 (c) John Stockton, near London.                Mail ?.?.Stockton@physics.org
  Web  <http://www.merlyn.demon.co.uk/> - FAQish topics, acronyms, and links.

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#22922 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

Dr J R Stockton <J.R.Stockton@physics.org> wrote on 31 jan 2014 in 
comp.lang.javascript:

> In comp.lang.javascript message <XnsA2C571A54D08Beejj99@194.109.133.133>
> , Thu, 30 Jan 2014 11:10:18, Evertjan. <exxjxw.hannivoort@inter.nl.net>
> posted:
> 
>>btw, the resistance of water though a tube, when the flow is low and so
>>laminal, follows Ohm's law by having a fixed resistance;
> 
> Not true.  The flow is proportional to the pressure difference at low
> flow rated, but what you describe is not the law of Georg Simon Ohm.  It
> is more nearly a simplified case of Darcy's law; the Hagenƒ "Poiseuille
> equation applies.  Ohm's Law is specifically electrical.

"follows" I wrote, but you are right, John, it is not fixed.

Our mind play us tricks, we want simple exact answers.

The apple falling from the tree does not exactly behave as Newton predicted,
not even theoretically, "as" on the move, its weight increases,
and in practice by air density and perhaps Bernoulli's principle.

On the other hand, Ohm's law in electrics is also only a theoretical law,
als it presumes all values to be "pure" and unchanging in time.

I long ago experimented with negative resistance, due to the tunnel effect 
in special diodes, defying a certain level of my "common sense". 

Should we call/have called this negative resistance "negative impedance",
as it is absent in constant direct current.

<http://en.wikipedia.org/wiki/Negative_resistance>

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

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#22946 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

In comp.lang.javascript message <XnsA2C760BAFB0E9eejj99@194.109.133.133>
, Sat, 1 Feb 2014 09:30:32, Evertjan. <exxjxw.hannivoort@inter.nl.net>
posted:

>The apple falling from the tree does not exactly behave as Newton predicted,
>not even theoretically, "as" on the move, its weight increases,
>and in practice by air density and perhaps Bernoulli's principle.

Do not confuse the increase in weight due to the decrease in altitude
with the relativistic increase in mass due to increased speed.

Impedance reflects not just the quadrature component.

See <http://nl.wikipedia.org/wiki/Impedantie> - and correct Google's
translation of "Elektriciteitsleer"!

-- 
 (c) John Stockton, Surrey, UK.  ¬@merlyn.demon.co.uk   Turnpike v6.05   MIME.
   Web  <http://www.merlyn.demon.co.uk/> - FAQish topics, acronyms, & links.

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#22947 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

Dr J R Stockton <reply1400@merlyn.demon.co.uk.invalid> wrote on 02 feb
2014 in comp.lang.javascript: 

> In comp.lang.javascript message <XnsA2C760BAFB0E9eejj99@194.109.133.133>
> , Sat, 1 Feb 2014 09:30:32, Evertjan. <exxjxw.hannivoort@inter.nl.net>
> posted:
> 
>>The apple falling from the tree does not exactly behave as Newton
>>predicted, not even theoretically, "as" on the move, its weight
>>increases, and in practice by air density and perhaps Bernoulli's
>>principle. 
> 
> Do not confuse the increase in weight due to the decrease in altitude
> with the relativistic increase in mass due to increased speed.

Did I? Methinks not.

> Impedance reflects not just the quadrature component.

That is a matter of definition.
 
> See <http://nl.wikipedia.org/wiki/Impedantie> 

I don't accept argumentation by [wikipedantic] authority.

> and correct Google's translation of "Elektriciteitsleer"!

Why should I? 
Into what language?
Papiamento perhaps?
btw, why the capital "E"?

I like this outdated Dutch word "elektriciteitsleer", even the vague 
feeling it could perhaps also mean "electricity leather".

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

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#22948 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

On Mon, 03 Feb 2014 01:15:21 +0100, "Evertjan."
<exxjxw.hannivoort@inter.nl.net> wrote:

>Dr J R Stockton <reply1400@merlyn.demon.co.uk.invalid> wrote on 02 feb
>2014 in comp.lang.javascript: 

  <snip>
>> Impedance reflects not just the quadrature component.
>
>That is a matter of definition.
  <snip>

Yes indeed! Unfortunately, your definition differs from everyone
else's. Even the Oxford dictionary defines impedance as the whole
thing, with a resistive component and a reactive component.

  John

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#22949 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

In article <vkbve9pkmh1pctli55ol37vg7sb93g0km9@4ax.com>, John Harris
<niam@jghnorth.org.uk.invalid> wrote:

> On Mon, 03 Feb 2014 01:15:21 +0100, "Evertjan."
> <exxjxw.hannivoort@inter.nl.net> wrote:
> 
> >Dr J R Stockton <reply1400@merlyn.demon.co.uk.invalid> wrote on 02 feb
> >2014 in comp.lang.javascript: 
> 
>   <snip>
> >> Impedance reflects not just the quadrature component.
> >
> >That is a matter of definition.
>   <snip>
> 
> Yes indeed! Unfortunately, your definition differs from everyone
> else's. Even the Oxford dictionary defines impedance as the whole
> thing, with a resistive component and a reactive component.

And this has always been the case, so I don't know where Evertjan is
getting his funny ideas from.

-- 
"People don't buy Microsoft for quality, they buy it for compatibility
with what Bob in accounting bought last year. Trace it back - they buy
Microsoft because the IBM Selectric didn't suck much" - P Seebach, afc

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#22950 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

Tim Streater <timstreater@greenbee.net> wrote on 03 feb 2014 in 
comp.lang.javascript:

>> >> Impedance reflects not just the quadrature component.
>> >
>> >That is a matter of definition.
>>   <snip>
>> 
>> Yes indeed! Unfortunately, your definition differs from everyone
>> else's. Even the Oxford dictionary defines impedance as the whole
>> thing, with a resistive component and a reactive component.

Even so, it is just a matter of definition.

> And this has always been the case, so I don't know where Evertjan is

Wow, you "all" seem to love being right about a definition. 
And I don't think you perseive this as unfortunate, Tim.
I would prefer to discuss what is happening in electricity and elsewhere.

I define impedance in sensu strictior as you do the reactive component.

But why quibble on that? 

I don't think discussing on authority, the OED no doubt, has much sense, as 
long as we understand eachother's perceived definitions.

Yes, I know that is not the christian way of discussion.

Impedance [being truly reactive], cannot disipate energy as heat,
that needs a resistance, being purely resistive.

Part of this even explains Ohm's law:

disipation p = v x i, 
and such tension can ony be seen across a resistor having
resistance r = v / i [Ohm strictior].

so the tension drop v = i^2 x r
and the resistance must be r = v / i^2
meaning that if the current is zero and the tension not, 
the resistance must be infinite.

Energy cannot be dissipated by inductance [your reactive part],
that way energy can only be reflected 
or sent to elsewhere either ad infinitum or where it finds resistance.

In practice, there is no purety, as even a pure constant current must be 
switched on, and of again, at one time or another. 

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

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#22955 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

In article <XnsA2C9B70FB86C1eejj99@194.109.133.133>, Evertjan.
<exxjxw.hannivoort@inter.nl.net> wrote:

> Tim Streater <timstreater@greenbee.net> wrote on 03 feb 2014 in 
> comp.lang.javascript:
> 
> >> >> Impedance reflects not just the quadrature component.
> >> >
> >> >That is a matter of definition.
> >>   <snip>
> >> 
> >> Yes indeed! Unfortunately, your definition differs from everyone
> >> else's. Even the Oxford dictionary defines impedance as the whole
> >> thing, with a resistive component and a reactive component.
> 
> Even so, it is just a matter of definition.
> 
> > And this has always been the case, so I don't know where Evertjan is
> 
> Wow, you "all" seem to love being right about a definition. 
> And I don't think you perseive this as unfortunate, Tim.
> I would prefer to discuss what is happening in electricity and elsewhere.
> 
> I define impedance in sensu strictior as you do the reactive component.
> 
> But why quibble on that? 
> 
> I don't think discussing on authority, the OED no doubt, has much sense, as 
> long as we understand eachother's perceived definitions.

Are you Humpty Dumpty? Try this:

  <https://en.wikipedia.org/wiki/Impedance_(electrical)>

which matches what I was taught at University.

-- 
"People don't buy Microsoft for quality, they buy it for compatibility
with what Bob in accounting bought last year. Trace it back - they buy
Microsoft because the IBM Selectric didn't suck much" - P Seebach, afc

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#22980 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

Tim Streater <timstreater@greenbee.net> wrote on 03 feb 2014 in
comp.lang.javascript: 

> In article <XnsA2C9B70FB86C1eejj99@194.109.133.133>, Evertjan.
> <exxjxw.hannivoort@inter.nl.net> wrote:
>> I define impedance in sensu strictior as you do the reactive component.
>> 
>> But why quibble on that? 
>> 
>> I don't think discussing on authority, the OED no doubt, has much
>> sense, as long as we understand eachother's perceived definitions.
> 
> Are you Humpty Dumpty? Try this:
> 
>   <https://en.wikipedia.org/wiki/Impedance_(electrical)>
> 
> which matches what I was taught at University.

Perhaps, but it seems you are not interested in the matter at hand,
only in showing off by authority.

A very christian way of discussion, indeed.

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

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#22987 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

On Mon, 03 Feb 2014 17:59:44 +0100, "Evertjan."
<exxjxw.hannivoort@inter.nl.net> wrote:


  <snip>
>I define impedance in sensu strictior as you do the reactive component.
  <snip>

In the equation
  E = I*Z
I call Z, a complex number, the impedance. What do you call it? Or do
you refuse to give it a name?

  John

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#23016 — Re: "impedance mismatch", was: Re: JavaScript unfairly blamed?

John Harris <niam@jghnorth.org.uk.invalid> wrote on 04 feb 2014 in 
comp.lang.javascript:

> On Mon, 03 Feb 2014 17:59:44 +0100, "Evertjan."
> <exxjxw.hannivoort@inter.nl.net> wrote:
>   <snip>
>>I define impedance in sensu strictior as you do the reactive component.
>   <snip>
> 
> In the equation
>   E = I*Z
> I call Z, 

Good for you.

>  a complex number,

Is it? 
Why would it be?

> the impedance.

I give you permission to do that, 
if you want that permission.

I gave my children names, 
and I call tham by these names,
but that did not define them,
I am glad to say.

If I knew what you are talking about,
I might disagree in the sense that I wouldn't call it that.

Then again I might not and would.

> What do you call it? 

Should I?

> Or do you refuse to give it a name?

Give what a name?
Why refuse?
Are you ordering me to? 

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

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