Peter T. Daniels ran out of electrical outlets; states rewiring entire house to be the only feasible solution.
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From: Mike Barnes on 30 Mar 2010 03:23 Jerry Friedman <jerry_friedman(a)yahoo.com>: >On Mar 29, 11:58�am, Mike Barnes <mikebar...(a)bluebottle.com> wrote: >> j...(a)specsol.spam.sux.com: >> >> >> >> >In sci.physics Mike Barnes <mikebar...(a)bluebottle.com> wrote: >> >> j...(a)specsol.spam.sux.com: >> >>>In sci.physics Mike Barnes <mikebar...(a)bluebottle.com> wrote: >> >>>> Hatunen <hatu...(a)cox.net>: >> >>>>>On Sat, 27 Mar 2010 09:29:58 +0000, Mike Barnes >> >>>>><mikebar...(a)bluebottle.com> wrote: >> >> >>>>>>Hatunen <hatu...(a)cox.net>: >> >>>>>>>On Fri, 26 Mar 2010 08:06:21 +0000, Jonathan de Boyne Pollard >> >>>>>>><J.deBoynePollard-newsgro...(a)NTLWorld.COM> wrote: >> >>>>>>>>[...] >> >>>>>>>>energy being delivered, the amount of which is >> >>>>>>>>determined by the wattage, >> >> >>>>>>>I suppose one might casually say that, but in fact the power >> >>>>>>>(wattage) is a function of the current and resistance, not >> >>>>>>>vise-versa. >> >> >>>>>>How so? >> >> >>>>>Power is a result of passing a current through a resistance; >> >>>>>current and rsistance aren't a result of power. >> >> >>>> But it seems to me equally valid to say that current is the result of >> >>>> generating power in a resistance. You can't pass current without >> >>>> generating power, and you can't generate power without passing current. >> >>>> They are two sides of the same of coin. It seems wrong to me to insist >> >>>> (as you seemed to be doing) that one is the cause of the other. >> >> >>>> [X-posting to sci.physics with some trepidation] >> >> >>>A resistance can not generate power, it can only dissipate it. >> >> >> You won't find me disagreeing with that (but I don't see the relevance). >> >> >>>The power dissipated in a resistance is a function of the resistance and >> >>>the externally generated voltage applied to the resistance. >> >> >> Ditto. >> >> >The relevance is that the phrase "is the result of generating power in a >> >resistance" is nonsense. >> >> I was struggling for the proper way to express the idea, and was unhappy >> with "generating", but I wouldn't go so far as to call it "nonsense". >> What would *you* call the process of producing the energy that has to be >> dissipated? >> >> [Newsgroups restored. Please don't mess with the follow-ups if you want >> any further response.] > >In my experience, "dissipating power" in a resistor means the rate of >conversion of electrical energy to heat, not the rate of dissipation >of heat into the environment, if that's how you're understanding it. Interesting point. Thanks. I didn't use the term "dissipating power" myself, but you've helped explain what Jim meant, and you've helped me express my point better. So I'll say instead (responding to "power (wattage) is a function of the current and resistance, not vise-versa"): "But it seems to me equally valid to say that current is the result of converting electrical power to heat in a resistance. You can't pass current without converting power, and you can't convert power without passing current. They are two sides of the same of coin. It seems wrong to me to insist (as [Hatunen] seemed to be doing) that one is the cause of the other." -- Mike Barnes Cheshire, England
From: Richard Chambers on 30 Mar 2010 08:29 Mike Barnes wrote > Jerry Friedman wrote: >>In my experience, "dissipating power" in a resistor means the rate of >>conversion of electrical energy to heat, not the rate of dissipation >>of heat into the environment, if that's how you're understanding it. > > Interesting point. Thanks. I didn't use the term "dissipating power" > myself, but you've helped explain what Jim meant, and you've helped me > express my point better. So I'll say instead (responding to "power > (wattage) is a function of the current and resistance, not vise-versa"): > > "But it seems to me equally valid to say that current is the result > of converting electrical power to heat in a resistance. You can't > pass current without converting power, and you can't convert power > without passing current. They are two sides of the same of coin. It > seems wrong to me to insist (as [Hatunen] seemed to be doing) that > one is the cause of the other." Electrical power is, in all important respects, the equivalent of mechanical power. In order to generate electrical power, you have to push hard against the electromagnetic forces that arise, as a natural reaction, within the generator. The harder you push (to keep the generator turning at the required speed), the more electrical power you produce. The more electrical power the generator provides to the customer, the greater the electromagnetic forces become, within the generator, preventing you from getting more electrical power out of the generator than you have put in as mechanical power. Stop pushing, and the generator reacts by ceasing to produce electrical power. The physicist's Law of Conservation of Energy is remorseless. Resistances do not enter into the discussion when you are discussing the generation of electricity. How do you choose to use this electrical power, once you have generated it? You might choose to use the power to make an electric train pull ten coaches at 150km/hour along a railway track. In this case, electrical resistance, once again, does not enter into the discussion. The electric motor in the train takes the electric power, and uses it to create an electromagnetic force that can be used to drive the train. The mechanical energy (of motion) that you have put into the train is subsequently converted into heat by mechanical friction and wind resistance. This is no different, in principle, from the heat production the caveman obtained from rubbing two sticks together. It is the conversion of mechanical energy into heat. Once again, electrical resistance (as distinct from mechanical friction/resistance) has not entered into our description of the use we have made of the electrical power we have generated. Alternatively, you might choose to use your electricity to power an electric fire. Only in this special and particular case do we have a situation where electrical resistance is relevant to the physicist's description of the process. And this apparent relevance is incidental, rather than basic. The description that works for all cases, whether for electric trains or electric fires, is the one that proposes that electric power is the voltage multiplied by the current. This description has an analogue in mechnical physice, which proposes that mechanical power is the mechanical force multiplied by the speed. (i.e. The heavier the car, and the faster you want it to go, the more powerful the engine needs to be, and the more fuel you will need to use). In this description, "voltage" is the analogue of "force", and "current" is the analogue of "speed". I do not understand why we are posting all this to alt.religion.kibology (where it is probably not relevant), or to sci.physics (where it is too trivial and basic). My apologies to both groups if this is a nuisance. I have done so only because everybody else seems to be doing it. What is "kibology", anyway? I have looked it up in my dictionary, and there is no entry between "kiblah" and "kibosh". Richard Chambers Leeds UK. www.metercare.co.uk
From: David DeLaney on 30 Mar 2010 03:51 Richard Chambers <richard.chambers7_NoSpam_(a)ntlworld.net> wrote: >I do not understand why we are posting all this to alt.religion.kibology >(where it is probably not relevant), because there's a physicist and a former physicist participating from there? And because You're Allowed to. >or to sci.physics (where it is too trivial and basic). I get the distinct impression that the person who's trying to say "V = IR Is Always Followed For All Materials And Times And Conditions And Each Material Has Exactly One R, Static And Eternal, Created By The Creator At The Creation" is posting from there; sci.physics attracts people who think they know more than they do about the subject, yes? >My apologies to both groups if this is a nuisance. I >have done so only because everybody else seems to be doing it. Not because your newsreader did it automatically? Well, that's something anyway. >What is "kibology", anyway? And the Doctroid scores again! (Twenty dollars. Same as in town. We will send remittal instructions as soon as you provide ICBM coordinates.) >I have looked it up in my dictionary, and there is no >entry between "kiblah" and "kibosh". <two opportunities in one post? It's like Halloween!> Your dictionary also probably left out "gullible"... Dave -- \/David DeLaney posting from dbd(a)vic.com "It's not the pot that grows the flower It's not the clock that slows the hour The definition's plain for anyone to see Love is all it takes to make a family" - R&P. VISUALIZE HAPPYNET VRbeable<BLINK> http://www.vic.com/~dbd/ - net.legends FAQ & Magic / I WUV you in all CAPS! --K.
From: Shelly on 30 Mar 2010 10:43 "Richard Chambers" <richard.chambers7_NoSpam_(a)ntlworld.net> wrote in message news:HsCdnRanHrUzcyzWnZ2dnUVZ8kqdnZ2d(a)brightview.co.uk... > I do not understand why we are posting all this to > alt.religion.kibology (where it is probably not relevant), *Everything* is relevant to Kibology. Alsotoo, you are Allowed. That is all. As you were, comrades! -- Shelly http://www.cat-sidh.net/blog
From: Shelly on 30 Mar 2010 10:44
"Shelly" <shelly(a)cat-sidh.net> wrote in message news:hot2mr$8s5$1(a)news.eternal-september.org... > "Richard Chambers" <richard.chambers7_NoSpam_(a)ntlworld.net> wrote in > message news:HsCdnRanHrUzcyzWnZ2dnUVZ8kqdnZ2d(a)brightview.co.uk... > >> I do not understand why we are posting all this to >> alt.religion.kibology (where it is probably not relevant), > > *Everything* is relevant to Kibology. Alsotoo, you are Allowed. Or irrelevant. Hard to tell the difference, sometimes, and I'm pretty sure it doesn't matter, anyway. -- Shelly http://www.cat-sidh.net/blog |