From: John Devereux on 11 Jul 2010 16:35 AM <thisthatandtheother(a)beherenow.org> writes: > On Sun, 11 Jul 2010 16:00:20 +0100, John Devereux <john(a)devereux.me.uk> > wrote: > >>One ampere-second does not have to mean that "one amp flowed for one >>second", > > It most certainly does. It is not an average. It most certainly does not. Any more than a kWh means one kilowatt of power was consumed over a one hour period. Or achieving a speed of 70mph means you actually travelled 70 miles for a one hour period. Amp-seconds is a measure of *integrated* charge. Do you always charge your 1200mAH NiMh batteries at 1200mA? > It is a rate. Not it is not. It is *amp-seconds*, not Amps per second! > If the measure will be shorter than one second, then another unit of > measure should be used. What, the "2 amp - half second"? Is that going to be a new SI unit? I'm afraid I've lost track of some of the nyms - but I do believe you must be that AlwaysWrong guy. -- John Devereux
From: John Devereux on 11 Jul 2010 16:42 Jim Thompson <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> writes: > On Sun, 11 Jul 2010 09:05:34 +0100, John Devereux > <john(a)devereux.me.uk> wrote: > >>Jim Thompson <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> writes: >> >>> In the next few days, when I have time, I will issue a mathematical >>> proof that Larkin is totally wrong. Watch for it ;-) >>> >>> Why haven't Win Hill and Phil Hobbs come to Larkin's defense? >>> >>> Bwahahahaha! >> >>I'm no Phil Hobbs, but isn't all this argument because we are conflating >>two different usages of "charge"? >> >>The "charge" on a capacitor, as somone pointed out already, is really >>charge *separation* (dilectric polarization). The Q=CV refers to a >>*separation* of charge, not an absolute quantity. The "absolute" charge >>- the total number of electrons minus the number of protons - is >>normally low or zero. Unless your whole circuit picks up an >>electrostatic charge from somewhere else. It is this "absolute" charge >>which is conserved, the "Q=CV" "charge" of normal electronics is >>not. Take a solar cell charging a battery for one obvious example. As >>Larkin would say, where did the charge come from? Photons don't carry >>charge! > > The photons entered the game from "outside the box" as someone opined. > > As for your "explanation" above... :-( > > If I'm so wrong and Larkin is so right, WHY don't Hill and Hobbs jump > to his defense? If you're so right, how come AlwaysWrong agrees with you? :) :) -- John Devereux
From: John Larkin on 11 Jul 2010 16:45 On Sun, 11 Jul 2010 21:35:09 +0100, John Devereux <john(a)devereux.me.uk> wrote: >AM <thisthatandtheother(a)beherenow.org> writes: > >> On Sun, 11 Jul 2010 16:00:20 +0100, John Devereux <john(a)devereux.me.uk> >> wrote: >> >>>One ampere-second does not have to mean that "one amp flowed for one >>>second", >> >> It most certainly does. It is not an average. > >It most certainly does not. Any more than a kWh means one kilowatt of >power was consumed over a one hour period. Or achieving a speed of 70mph >means you actually travelled 70 miles for a one hour period. > >Amp-seconds is a measure of *integrated* charge. Do you always charge >your 1200mAH NiMh batteries at 1200mA? > >> It is a rate. > >Not it is not. It is *amp-seconds*, not Amps per second! > >> If the measure will be shorter than one second, then another unit of >> measure should be used. > >What, the "2 amp - half second"? Is that going to be a new SI unit? > >I'm afraid I've lost track of some of the nyms - but I do believe you >must be that AlwaysWrong guy. AM = AlwaysMistaken. John
From: John Fields on 11 Jul 2010 16:47 On Sun, 11 Jul 2010 08:52:56 -0700, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >Yup. Energy is conserved in the restacking-the-caps case, but charge >isn't. That was my simple point all along. Thanks for the >confirmation. --- Earlier on you seem to have been vaccillating as you so often do when you're waiting for someone to slip and give you an answer you can claim you already knew, so do you now firmly believe that charge isn't conserved? Final answer, or are you going to dance around some more?
From: John Fields on 11 Jul 2010 17:20
On Sun, 11 Jul 2010 13:29:02 -0700, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >On Sun, 11 Jul 2010 12:34:41 -0700, AM ><thisthatandtheother(a)beherenow.org> wrote: > >>On Sun, 11 Jul 2010 16:00:20 +0100, John Devereux <john(a)devereux.me.uk> >>wrote: >> >>>One ampere-second does not have to mean that "one amp flowed for one >>>second", >> >> It most certainly does. It is not an average. >> >> It is a rate. > >No. It is an integral. > >> If the measure will be shorter than one second, then another unit of >>measure should be used. > >No, no, no! A coulomb is a coulomb. If a capacitor stores a coulomb of >charge, and you remove it all, you get a coulomb, one ampere-second, >out, and it doesn't matter how long you take to do it, or whether ths >discharge is constant, exponential, quarter-sine, or anything else. > >You can get one constant ampere for one second. Or get 0.1 amp for 10 >seconds. Or a thousand amps for a millisecond, if it's a suitable good >cap. > >It's like a gallon jug that contains one gallon of water: whether you >empty is fast or slow, uniformly or not, you always get a gallon in >the end. That's how much is in there! --- Yes, and that's why it's called a gallon instead of a 4 quart-second or something equally as goofy and why you should use coulomb instead of ampere-second unless there's a very good reason not to. Like playing Mr. Cutesy. |