Peter T. Daniels ran out of electrical outlets; states rewiring entire house to be the only feasible solution.
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From: PaulJK on 30 Mar 2010 02:04 Mike Barnes wrote: > Jonathan de Boyne Pollard <J.deBoynePollard-newsgroups(a)NTLWorld.COM>: >>> >>>>> >>>>> But as you've snipped my attribution, how does anyone know you are >>>>> talking to me? >>>>> >>>> The same way that you yourself obviously did, of course. Don't >>>> assume that the rest of the world is incapable of doing that. The >>>> rest of the world will use the References: header which specifies >>>> exactly and unequivocally which post is being replied to, just like >>>> you did when you looked at the thread summary in gnus. Attributions >>>> are mere duplications of [...] >>>> >>> You shouldn't assume that the rest of the world will use the >>> References header, [...] >>> >> Yes, we should. That's what it's always been there for, and as I said, >> we're coming up on the 25th anniversary of the release of the first >> threaded newsreader. M. Nick's newsreader, gnus, uses the References: >> header to present its thread summary. > > You shouldn't assume that the rest of the world will look outside the > body of the message to see who wrote the quoted material, even though it > is obviously possible to do so. Just because they can, doesn't mean they > will. And even though they can, it's bad manners to knowingly force them to. It's such a bad manner, that only a single person here does it. AFAICT, nobody else here does it on purpose. pjk
From: PaulJK on 30 Mar 2010 02:10 Otto Bahn wrote: > "Adam Funk" <a24061(a)ducksburg.com> wrote > >>> If that is so, then please tell me how you define "resistance". >> >> It's futile, Doctroid. > > What's impeding it? Wanna hear some Vogon poetry? pjk
From: PaulJK on 30 Mar 2010 02:26 jimp(a)specsol.spam.sux.com wrote: > In sci.physics Doctroid <doctroid(a)mailinator.com> wrote: >> In article <nq6787-qkc.ln1(a)mail.specsol.com>, jimp(a)specsol.spam.sux.com >> wrote: >> >>> All things obey Ohm's law exactly because R=V/I is the definition of >>> resistance. >> >> In that case I hereby announce Doctroid's Law which states that >> >> V = D * C >> >> where V is the electrical potential across a device, and C is the total >> mass of chocolate consumed in the past year by the person who measures >> V. D is the device's Doctroidance, which is in fact defined by D = V / >> C, and of course is not constant. Therefore Doctroid's law always holds >> for all circumstances. >> >> It is also perfectly useless. As is Ohm's Law, if you consider it to be >> solely a definition of resistance: it has no predictive power. > > Sorry, the universe, empirical data, and better than a century of electrical > engineering and physics disagree with your conclusion. > > And obviously the phrase "characteristic curve" is meaningless to you. A homework for Doctroid and P.Moylan http://www.allaboutcircuits.com/worksheets/diode1.html just trying to help you to stop embarrassing yourself with high school physics. pjk
From: Peter Duncanson (BrE) on 30 Mar 2010 07:07 On Tue, 30 Mar 2010 17:57:10 +1200, "PaulJK" <paul.kriha(a)paradise.net.nz> wrote: > >At every point in time and at every point inside the body >of a resistive conductor the Ohm's law applies with 100% >accuracy. It is applicable even when the conductors are >never completely homogeneous and never absolutely linear. > >(Excepting conditions in the super conductive environment.) That assumes that the current results from a potential difference, a voltage. If a closed circuit, a resistive ring for instance, is put in a varying magnetic field an induced current will flow but no potential difference will be created. -- Peter Duncanson, UK (in alt.usage.english)
From: Doctroid on 30 Mar 2010 08:07
In article <hos036$3mk$1(a)news.eternal-september.org>, "PaulJK" <paul.kriha(a)paradise.net.nz> wrote: > Peter Moylan wrote: > > PaulJK wrote: > >> Doctroid wrote: > >>> In article <homphq$91l$1(a)news.eternal-september.org>, > >>> "PaulJK" <paul.kriha(a)paradise.net.nz> wrote: > >>> > >>>> Voltage and current are proportional to each other. > >>>> It is therefore sufficient to say that damage is proportional > >>>> to one of them. > >>> Only in materials and voltage/current ranges where Ohm's "law" is > >>> obeyed. And if damage is occurring, it probably isn't. > >> > >> Ohm's law is always obeyed in all aparatus made by humans. > >> > > Except when it isn't - which is most of the time. > > > > It's true that a great many resistors are nearly linear, i.e. they can > > be said to obey Ohm's law to a reasonable degree of accuracy, provided > > that you don't go beyond their design limits. > > > > It's equally true that some resistive devices are *deliberately* made to > > be nonlinear. A semiconductor diode, for example, would be totally > > useless if it obeyed Ohm's law. > > I see you didn't have Ohm's law in your high school? > What has nonlinearity to do with it? Absolutely nothing. > > At every point in time and at every point inside the body > of a resistive conductor the Ohm's law applies with 100% > accuracy. It is applicable even when the conductors are > never completely homogeneous and never absolutely linear. > > (Excepting conditions in the super conductive environment.) > > pjk I think the problem you are having is that you think Ohm's Law is "V = IR". It's not. Ohm's law is the statement "There is a quantity R, defined by the relation V = IR, which is independent of V and I." Often one says "V = IR" is Ohm's law, because that's a convenient shorthand; but that equation is merely a definition of R, and has no real content in the absence of an observation that R doesn't depend on V and I. Which is true, for many materials, over a wide range of V and I, to a good approximation; but not for all materials in all circumstances to infinite precision. All materials obey V = IR, by the definition of R, but not all materials obey Ohm's Law. Anyone wishing to take this up with me further may write to me at rsholmes at physics dot syr dot edu. -- Sig available on request. - Doctroid |