Win Hill: Inverse Marx Generator ??
in [Design]
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From: John Larkin on 11 Jul 2010 12:20 On Sun, 11 Jul 2010 08:26:22 -0700, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >On Sun, 11 Jul 2010 05:27:16 -0500, John Fields ><jfields(a)austininstruments.com> wrote: > >>On Sat, 10 Jul 2010 18:13:29 -0700, John Larkin >><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >> >>>On Sat, 10 Jul 2010 19:13:31 -0500, "Andrew" <anbyvbel(a)yahoo.com> >>>wrote: >>> >>>>"John Larkin" <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in message >>>>news:c19h36hekre5kldo38cmdt465f5consr42(a)4ax.com... >>>>> On Sat, 10 Jul 2010 11:31:15 -0500, Vladimir Vassilevsky >>>>> <nospam(a)nowhere.com> wrote: >>>>> >>>>>>John Larkin wrote: >>>>>> >>>>>>> Exactly the point I've been making. Some EEs seem to think that charge >>>>>>> is always conserved. Some physicists seem to think that energy is >>>>>>> always conserved. They can't both be right. >>>>>>> >>>>>>> I'll side with the physicists on this one. >>>>>> >>>>>> >>>>>>There is no physical laws of "conservation of ...". >>>>>>There are, however, artificially designed parameters such as "energy", >>>>>>"charge", "momentum", etc. Those parameters are *defined* in such way >>>>>>that their value is preserved through certain transformations of a >>>>>>physical system. The only purpose of this is simplification of math; so >>>>>>it is possible to balance the states of a system instead of solving >>>>>>differential equations. >>>>>> >>>>> >>>>> But it's convenient to balance the books by calculating the total >>>>> energy in a system and assuming it's constant. That can short-cut all >>>>> sorts of circuit and signal processing problems, avoiding the calculus >>>>> you suggest. I know of no cases where the energy balance thing has >>>>> been violated. It would make the front page of the New York Times if >>>>> it ever were. >>>> >>>>Every time it found to be violated new item was added to the definiton of >>>>"energy" to make it constant. >>>> >>>>Last time it was mc^2 if I remember correctly. >>> >>>Well, that was over 100 years ago. And even that addition is >>>irrelevant to electronic design. >> >>--- >>Tell that to Tektronix. > >Do they still make CRTs? > >John I think the highest voltage Tek CRT was around 28KV, in the 519. Relativistic effects are still small at 30KV, about 5% on mass, 1.5% on velocity, probably small enough to ignore. John
From: John Fields on 11 Jul 2010 12:20 On Sun, 11 Jul 2010 08:36:11 -0700, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >On Sun, 11 Jul 2010 08:14:39 -0500, John Fields ><jfields(a)austininstruments.com> wrote: > >>On Sun, 11 Jul 2010 13:47:20 +0100, John Devereux >><john(a)devereux.me.uk> wrote: >> >>>John Fields <jfields(a)austininstruments.com> writes: >>> >>>> On Sat, 10 Jul 2010 10:13:27 -0700, John Larkin >>>> <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>> >>>> >>>>>OK, enlighten me. >>>> >>>> --- >>>> OK. >>>> --- >>>> >>>>>Slap a 1-ohm resistor across the 1F/1v cap and discharge it. You'll >>>>>get 1 ampere-second out of it eventually. >>>> >>>> --- >>>> Sorry, Charlie, but no. >>>> >>>> An ampere-second is the amount of charge transferred by a current of 1 >>>> ampere in one second. >>> >>>That is, 1 coulomb. >>> >>>> >>>> In your example the current will be one ampere when the resistor is >>>> first connected, but will have decayed to about 368 mA after one >>>> second has passed, so there's no way you'll get one ampere-second out >>>> of it. >>> >>>What on earth are you talking about? This is pretty much the >>>*definition* of capacitance. I.e., from Q = CV = "Ampere Seconds". >>> >>>No wonder John's having trouble convincing you of anything... >> >>--- >>Not of anything, just of some things. >> >>About the ampere-seconds thing though: >> >>If you connect a 1VDC supply across a 1 ohm resistor for 1 second then >>the amount of charge tranferred will be 1 coulomb. >> >>Then, since it got transferred in one second, the rate at which it was >>tranferred was one coulomb per second, which is one ampere. >> >> >>Now, replace the DC power supply with a capacitor charged to one volt, >>connect it to the resistor, and then disconnect it after one second. >> >>Will one coulomb of charge have been transferred? > > >Quoting myself, > >"Slap a 1-ohm resistor across the 1F/1v cap and discharge it. You'll >get 1 ampere-second out of it eventually." > >How did you miss the words "discharge" and "eventually"? I worded the >situation as carefully as I could, figuring some whiney dork or >another would get pretend-lawyer pickey. Sigh. --- I didn't miss them, I just thought someone as vague as you are coudn't possibly have meant "coulomb" since it's a much less confusing term. So you prefer ampere-second to coulomb? --- >How many ampere-seconds would you get if it was discharged by a 10 ohm >resistor? --- Depends on how long you left it on there.
From: John Fields on 11 Jul 2010 12:21 On Sun, 11 Jul 2010 08:41:01 -0700, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >On Sun, 11 Jul 2010 01:54:56 -0400, "Michael A. Terrell" ><mike.terrell(a)earthlink.net> wrote: > >> >>Vladimir Vassilevsky wrote: >>> >>> John Larkin wrote: >>> >>> > I'm an engineer. I design circuits. Philosophy is useless to me unless >>> > it allows me to quantify and measure things and predict what the >>> > numbers will mean. >>> >>> Yea, this is what good soldier Schweik used to say: >>> >>> "When a car runs out of gas, it stops. Even after been faced with this >>> obvious fact, they dare to talk about momentum". >> >> >> Really? You come to a dead stop the instant you run out of gas? I >>coasted a little over seven miles one night, after the engine died. I >>rolled to a stop about 50 feet from a gas pump. Of course, American >>vehicles have a marvelous invention called a 'Clutch'. > >Seven miles? Downhill? --- No, uphill...
From: Richard Henry on 11 Jul 2010 12:34 On Jul 11, 8:46 am, Jim Thompson <To-Email-Use-The-Envelope-I...(a)On-My- Web-Site.com> wrote: > On Sat, 10 Jul 2010 09:07:22 -0700, John Larkin > > > > <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: > >On Sat, 10 Jul 2010 11:35:35 -0400, "tm" <no...(a)msc.com> wrote: > > >>"John Larkin" <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote in message > >>news:o61h36lt8fvhsc00mrc9824ju0jd4hml8s(a)4ax.com... > > >>> To celebrate the 21st century, I have composed a new riddle: > > >>> Start with a 4 farad cap charged to 0.5 volts. Q = 2 coulombs. > > >>> Carefully saw it in half, without discharging it, such as to have two > >>> caps, each 2 farads, each charged to 0.5 volts. The total charge of > >>> the two caps remains 2 coulombs, whether you connect them in parallel > >>> or consider them separately. > > >>> Now stack them in series. The result is a 1F cap charged to 1 volt. > >>> That has a charge of 1 coulomb. Where did the other coulomb go? > > >>> I think this is a better riddle. > > >>> John > > >>One should not confuse charge with energy. > > >Exactly the point I've been making. Some EEs seem to think that charge > >is always conserved. Some physicists seem to think that energy is > >always conserved. They can't both be right. > > >I'll side with the physicists on this one. > > >John > > "Side" with whomever you like. But both "laws" apply simultaneously. > Energy is always conserved. Charge gets moved around. Whether you find it to be "conserved" or not depends on where you look for it.
From: tm on 11 Jul 2010 12:35
"John Fields" <jfields(a)austininstruments.com> wrote in message news:qrrj36paghkr1tvaphhr4eqf7b1qpausul(a)4ax.com... > On Sun, 11 Jul 2010 08:41:01 -0700, John Larkin > <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: > >>On Sun, 11 Jul 2010 01:54:56 -0400, "Michael A. Terrell" >><mike.terrell(a)earthlink.net> wrote: >> >>> >>>Vladimir Vassilevsky wrote: >>>> >>>> John Larkin wrote: >>>> >>>> > I'm an engineer. I design circuits. Philosophy is useless to me >>>> > unless >>>> > it allows me to quantify and measure things and predict what the >>>> > numbers will mean. >>>> >>>> Yea, this is what good soldier Schweik used to say: >>>> >>>> "When a car runs out of gas, it stops. Even after been faced with this >>>> obvious fact, they dare to talk about momentum". >>> >>> >>> Really? You come to a dead stop the instant you run out of gas? I >>>coasted a little over seven miles one night, after the engine died. I >>>rolled to a stop about 50 feet from a gas pump. Of course, American >>>vehicles have a marvelous invention called a 'Clutch'. >> >>Seven miles? Downhill? > > --- > No, uphill... > Both ways... --- news://freenews.netfront.net/ - complaints: news(a)netfront.net --- |