Let's Take A Vote...
in [Design]
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From: Robert Baer on 24 Jul 2010 04:03 Rich Grise wrote: > On Fri, 23 Jul 2010 15:52:06 -0700, Jim Thompson wrote: > >> Let's Take A Vote... >> >> While I write this up, hopefully sometime this weekend, let me ask for >> votes... >> >> How many think, as Larkin opines, "charge is not conserved" ?? >> >> How many think charge IS conserved ?? >> >> Just curious what I'm up against here. >> > This is probably simple to someone like Richard Feynman, but if it isn't > "conserved," where does it go? > > Thanks, > Rich > [wondering if I should have posted this as The Philosophizer. ;-) ]\ > You have never heard of electrons dropping in the bit bucket? You can tell by way of the oil tracks from Millikan's experiment.
From: Robert Baer on 24 Jul 2010 04:04 Rich Grise wrote: > On Fri, 23 Jul 2010 17:38:45 -0700, John Larkin wrote: > >> On Fri, 23 Jul 2010 19:30:25 -0500, John Fields >> <jfields(a)austininstruments.com> wrote: >> >>> On Fri, 23 Jul 2010 15:52:06 -0700, Jim Thompson >>> <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: >>> >>>> Let's Take A Vote... >>>> >>>> While I write this up, hopefully sometime this weekend, let me ask for >>>> votes... >>>> >>>> How many think, as Larkin opines, "charge is not conserved" ?? >>>> >>>> How many think charge IS conserved ?? >>>> >>>> Just curious what I'm up against here. >>> --- >>> Cordially, Jim, >>> >>> All you're up against is Larkin's sophistry, and whether any of us votes >>> as to whether charge is conserved or not is immaterial, since nature >>> rules. >>> >>> Post what you've got and let the chips fall where they may, there's >>> always Wikipedia which supports your position: >>> >>> http://en.wikipedia.org/wiki/Electric_charge#Conservation_of_electric_charge >>> >>> >>> On the other hand, if Larkin's right and energy is conserved but charge >>> isn't, then since charge is a measure of force, unbalanced lost charge >>> might be able to be used for propulsion. >> Charge is measured in coulombs. Force is measured in newtons. So how is >> charge "a measure of force"? >> > What's "electromotive force?" Its units are "volts," right? > > What was the original question? > > Thanks, > Rich > > See my previous posting..
From: Richard Henry on 24 Jul 2010 04:22 On Jul 24, 12:59 am, Robert Baer <robertb...(a)localnet.com> wrote: > John Larkin wrote: > > On Fri, 23 Jul 2010 19:30:25 -0500, John Fields > > <jfie...(a)austininstruments.com> wrote: > > >> On Fri, 23 Jul 2010 15:52:06 -0700, Jim Thompson > >> <To-Email-Use-The-Envelope-I...(a)On-My-Web-Site.com> wrote: > > >>> Let's Take A Vote... > > >>> While I write this up, hopefully sometime this weekend, let me ask for > >>> votes... > > >>> How many think, as Larkin opines, "charge is not conserved" ?? > > >>> How many think charge IS conserved ?? > > >>> Just curious what I'm up against here. > >> --- > >> Cordially, Jim, > > >> All you're up against is Larkin's sophistry, and whether any of us > >> votes as to whether charge is conserved or not is immaterial, since > >> nature rules. > > >> Post what you've got and let the chips fall where they may, there's > >> always Wikipedia which supports your position: > > >>http://en.wikipedia.org/wiki/Electric_charge#Conservation_of_electric.... > > >> On the other hand, if Larkin's right and energy is conserved but > >> charge isn't, then since charge is a measure of force, unbalanced lost > >> charge might be able to be used for propulsion. > > > Charge is measured in coulombs. Force is measured in newtons. So how > > is charge "a measure of force"? > > > John > > Lessee... > *force (vector)F, dimensions : M L T^-2 (derived unit Newton). > *charge q, dimensions : Q (derived unit coulomb). > Hmmm absolutely no similarity; need a conversion factor that adds > the correct dimensions.... > Maybe as a wild guess try electric field strength (vector)E, M L > T^-2Q^-1 (derived unit volts/meter)? Volt = joule/coulomb Does that help?
From: John Devereux on 24 Jul 2010 04:24 Jim Thompson <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> writes: > Let's Take A Vote... > > While I write this up, hopefully sometime this weekend, let me ask for > votes... > > How many think, as Larkin opines, "charge is not conserved" ?? > > How many think charge IS conserved ?? > > Just curious what I'm up against here. It depends on the context and your definitions, as already pointed out and which you still refuse to provide. Are you using a definition which says capacitors store charge or not? Is the quantity Q=CV to be regarded as "charge" or not? Is charge "delivered" or does it "flow through"? *Without* any context, I would have said "charge is conserved". You don't need to spend three weeks proving this, just point to Kirchoff. But the context of the original thread was all abouit switched capacitors and whether the "capacitors charge" was always conserved when transfered to another. We routinely refer to the quantity Q=CV as the capacitors "charge", it is this quantity which is not conserved, I.e., you can sum them before and after the switching operation and it is different. Not sophistry, just a normal use of terms in a circuit description. And it is obvious that this was the intended usage, since otherwise the "charge of the capacitor" is always zero! Basically, our routine use of the word is ambiguous, you can easily "prove someone wrong" by assuming the opposite usage to that intended, -- John Devereux
From: Martin Brown on 24 Jul 2010 04:45
On 23/07/2010 23:52, Jim Thompson wrote: > Let's Take A Vote... > > While I write this up, hopefully sometime this weekend, let me ask for > votes... > > How many think, as Larkin opines, "charge is not conserved" ?? Hopefully not too many. But it is difficult to predict the behaviour of electronics engineers - about half of them think Einstein was wrong :( > > How many think charge IS conserved ?? Just about every physicist on the planet since Ben Franklin. It was the inconsistency of Ampere's Law with conservation of charge that led Maxwell to formulate his famous equations and show that oscillating fields of electromagnetic radiation travel at a constant speed c in a vacuum. > > Just curious what I'm up against here. > > ...Jim Thompson A idealised physics version of your original capacitor problem but without the switch can be stated as the following problem: Two identical metal spheres with capacitance C are used. Initially one is uncharged and the other with a charge Q They are brought together from infinity until they touch. Describe what happens and how the charge is distributed after they are in electrical contact. You can add an infinite ground plane under the experiment if it makes you feel better about the circuit analogue. Regards, Martin Brown |