9-11 First Responders See Loonylies Loser Tactics
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From: Remy McSwain on 24 Mar 2010 18:11 "Peter Webb" <webbfamily(a)DIESPAMDIEoptusnet.com.au> wrote in message news:4baa841d$0$1785$afc38c87(a)news.optusnet.com.au... > > "AllYou!" <idaman(a)conversent.net> wrote in message > news:fqqdnb0isbc-5TfWnZ2dnUVZ_uednZ2d(a)posted.choiceonecommunications... >> In news:4baa0937$0$1783$afc38c87(a)news.optusnet.com.au, >> Peter Webb <webbfamily(a)DIESPAMDIEoptusnet.com.au> mused: >>> "AllYou!" <idaman(a)conversent.net> wrote in message >>> news:uqCdnaa5sqElYzTWnZ2dnUVZ_o6dnZ2d(a)posted.choiceonecommunications... >> >>>> Notice that he's never given his opinion as to what forces he >>>> thinks were acting upon the upper block DURING THE COLLISION >>>> with the lower support structure? >>> >>> Well, this has been discussed. >>> >>> But as I keep pointing out, the forces literally do not enter >>> the equations for what happens after inelastic collisions (or >>> elastic ones, for that matter). >> >> And as I keep pointing out, the issue that was under debate, and >> remains so, isn't what happened AFTER the collision. The issue >> is what were the forces being exerted on the upper block DURING >> THE COLLISION. > > No. > > The forces that occur *during* a collision cannot be determined, > and do not form part of the equations of motion for an inelastic > collision. The equations for motion for an inelastic collision do not even apply to the situation of what is occurring DURING THE COLLISION, and so your continued references to them for that situation is a wrong-headed red herring. > http://en.wikipedia.org/wiki/Inelastic_collision > See any mention of forces? No? So why do you think the forces are > an issue during an inelastic collision? See any mention of DURING A COLLISION? NO? See any mention of AFTER A COLLISION? YES? "The formulas for the velocities after a one-dimensional collision are:" Do you see it now? "AFTER [] COLLISION"? So why would you ask me to look at those equations for anything that has to do with what happens DURING A COLLISION if the site itself says that those equations are only applicable for the velocities of the masses AFTER A COLLISION? Are you really that dense? As I've been explaining to you all along, your confusion stems from the fact that because this was an inelastic collision, and because you found those equations on a web site entitled "inelastic collisions", you've mistakenly concluded that those equations apply to a consideration of the dynamics of what happens DURING A COLLISION. But they do not. As that site clearly indicates, those equations are only for the purposes of determining the velocities of the masses involved in a collision, but only AFTER the collision, and not DURING THE COLLISION, when accelerations and forces are most definitely at work. Just admit your mistake, and be done with it.
From: Peter Webb on 24 Mar 2010 21:27 "Remy McSwain" <Paradis70080(a)gmail.com> wrote in message news:F9adnWvcXZVzjzfWnZ2dnUVZ_qqdnZ2d(a)giganews.com... > > "Peter Webb" <webbfamily(a)DIESPAMDIEoptusnet.com.au> wrote in message > news:4baa056c$0$11181$afc38c87(a)news.optusnet.com.au... >> >> "Remy McSwain" <Paradis70080(a)gmail.com> wrote in message >> news:mtudnUkl2_5cbjTWnZ2dnUVZ_sKdnZ2d(a)giganews.com... >>> >>> "Peter Webb" <webbfamily(a)DIESPAMDIEoptusnet.com.au> wrote in message >>> news:4ba96073$0$11705$afc38c87(a)news.optusnet.com.au... >>> >>> [snipped a bunch of lies by PW] > > Parse everything to death all you want so that you can continue your > campaign of obfuscation, but you know for certain that the context of that > statement was as a premise for the assertion that the lower structure had > no reason to fail as a result of the upper block falling on it because it > was designed to support that weight. You know this because you responded > many times to that argument. > > Moreover, the statement itself, when taken as a whole, and not parsed as > you keep doing so as to obfuscate the issue, is clearly indicating that > the "N" to which they refer is a reaction to "mg" (i.e., the weight of the > upper block). Not the result of resisting the momentum of the upper > block, but of the weight "(mg)" of the upper block. > No, they don't say that at all, at least not in the bit you quoted. > And the proof that this is so is contained in what followed in that > report. I don't know about the rest of the report. You didn't post it, and I haven't read it. > And before you go there, what followed in that report had been posted here > very many times by your KOOK brethren, and so you cannot claim that you > didn't know the context unless you lie, which, of course, you will. I can't recall seeing it. And you didn't post it. I haven't actually read everything on the internet. > And you can keep claiming that I've never told you what other force was at > play during that collision, but that's just another lie on your part. > I've said it all along, and I'll say it now. The force ignored by that > statement was F=(d/dt)mv. > No, that is just a definition of what force is. If you think there are additional forces at play, you should say what they are, not just provide a generic definition of "force". > And BTW, as to your response about your other mistake? "All I [you] did" > was entirely incorrect as it pertained to the question. What you did was > analogous to someone asking you what color the sky is, and you answering > that the ocean is deep. It's a valid comment, but it's wrong as it > pertains to the question. > No. Perhaps if you were to actually quote what I said .... > The question at hand was how much resistance the support structure > provided to the fall of the upper block, and your approach was to assume > zero as a premise to your answer. No. Perhaps if you were to actually quote what I said .... <aybe > Notwithstanding the fact that your approach was overly simplistic anyway, > it was nonsense as an answer to the question at hand. > > >>> Look, I'm tired of all of your shaking and baking and every other >>> kind of obfuscation you're tried to throw out there just to avoid >>> admitting your mistakes. As far as saying that the following >>> statement is "absolutely correct", you're dead wrong. >>> >>> "The only two relevant forces acting on the falling block are >>> gravity (mg) and an upward normal force (N) due to its interaction >>> with the lower section of the building." >>> >> >> Its correcr. There is no obfuscation; there never has been. >> >> >>> You want context, here's the context. A debate between AY and the >>> KOOK Henry was being waged as to whether or not the remaining lower >>> support structure of the towers failed because the upper block of >>> floors fell on it, or whether it failed for other reasons. The KOOK >>> kept saying that the proof it had fallen for other reasons was that >>> the support structure was designed to hold up the weight of the >>> upper block, and that this was the only force being exerted on it, >>> and yet, it didn't hold up. >>> >> >> I don't know what else they said, or whether it was correct. >> >> This statement: >> >> "The only two relevant forces acting on the falling block are gravity >> (mg) and an upward normal force (N) due to its interaction with the lower >> section of the building." >> >> This is correct. Unless you can point to some other "relevant force"; I >> have asked you this several times and you haven't. And you can't; what >> they said is correct. >> >> >>> You knew this was the context of that quote. You could not know >>> otherwise. Yet, in light of that context, you pronounced that >>> statement "absolutely correct". That's clearly wrong. >>> >> >> You provided zero context for their quote. I have not read the original >> document. How on earth could I know what else they said, and why would I >> care? The simple fact is that waht you said they said is correct, and >> derspite repeated questioning you have not said why you think it is >> wrong. >> >> So here is another chance. "The only two relevant forces acting on the >> falling block are gravity (mg) and an upward normal force (N) due to its >> interaction with the lower section of the building.". If you think this >> is wrong, you have to show either that these forces are not relevant, or >> there is another relevant force. >> >> So, go for it. What additional forces do you think there are, exactly? >> >> >> >> >>> Since then, you've tried to defend your position by claiming that, >>> by definition, the only force that could be exerted on a falling >>> body_is_gravity. >> >> No. I didn't say that. Again, if you want to accuse me of saying >> something incorrect, you should providemy exact words. I said nothing >> like that at all. >> >> >>> But that's not only contrary to the context in >>> which that statement was made, your claim is also contrary to the >>> statement. It doesn't say that the only force acting on the falling >>> block was gravity. It says there were two forces acting on that >>> body, and that the other was the reaction force of the lower >>> structure "due to its interaction". >>> >> >> Yes. >> >> They are the only two relevant forces. >> >> Unless you know of another? >> >> >>> So the falling body in that statement was interacting (i.e., >>> colliding) with a support structure. By definition, and in the >>> context of 911, this HAD to be the infamous collision of the falling >>> block with the lower structure. Do you know of any Newtonian >>> forceless collisions? We're not talking about quantum physics here, >>> and so remember context. >>> >> >> No. >> >> >>> You've tried to salvage your position by mischaracterizing the >>> condition in that statement as that of just a falling body because >>> only gravity acts on a falling body. >> >> No. >> >>> But that's not the condition >>> described by the statement. >> >> Its not even the claim of the statement, which clearly does not state >> that gravity is the only force. >> >> >>> The statement says that the falling >>> body is falling, AND interacting with the support structure. THAT >>> is the case of a collision, >> >> >> Without seeing their quote in context, I doubt it. Not that it matters, >> the statement is correct. >> >> >>> and in the case of a collision, and as >>> AY has correctly pointed out, Newton's second law of motion >>> F=(d/dt)mv is also going on. >>> >> >> Yes, that is the "upward normal force (N) due to its interaction with the >> lower section of the building." >> >> >> >>> YES, that means a force other than the weight of the upper block, >>> which means that the statement that weight, and the "normal upward" >>> reaction to it, were the only forces going on in that collision is >>> dead wrong. It was the force which resulted from the collision. >> >> "upward normal force (N) due to its interaction with the lower section of >> the building." The interaction in this case being the collision. >> >> >>> It >>> wasn't F=mg. It was F=(d/dt)mv. 'g' only served to establish the >>> maximum 'v'. >>> >>> Either way, that statement is not correct. Either way, you're >>> wrong to say that it was correct. >>> >>> The bottom line for you, and for the KOOK Henry, is that the >>> momentum of the upper block played a very significant role in the >>> failure of the lower support structure. >> >> Momentum is not a force. >> >> >>> Any way you slice it, that >>> change in momentum 'mv' by the function of 'd/dt' resulted in a >>> force which was the very reason that the support structure failed. >> >> Yes. >> >>> During the interaction between the two bodies, it was (d/dt)mv that >>> was acting upon the upper block. >>> >> >> Yes. Its interaction with the lower part of the building. >> >> >>> And BTW, you were also wrong to think that your analysis of the >>> collapse of the towers which ignored the resistance of the support >>> structures could answer the question of whether or not that support >>> structure offered any resistance to the collapse. That's a >>> self-contradicting position. Even a KOOK could see the error there. >>> >>> >> >> All I did was apply a classical analysis based upon an inelastic >> collision conserving momentum. Just like the web pages I pointed you at, >> and the many physics lectures I have attended on dynamics. >> >> If you think there are additional relevant forces, you should list them. >> Momentum is not a force. BTW, there is a third force, but its not >> relevant - air resistance. I assume that is why they used the word >> "relevant". There is absolutely nothing wrong with what they said; these >> are the only two relevant forces. >> Funny, you don't actually say what additional forces act on the falling block, and hence why you believe the quote is wrong. I answer your questions; why don't you answer mine?
From: Peter Webb on 24 Mar 2010 22:31 "Remy McSwain" <Paradis70080(a)gmail.com> wrote in message news:qOKdnRXFT6AKiTfWnZ2dnUVZ_rednZ2d(a)giganews.com... > > "Peter Webb" <webbfamily(a)DIESPAMDIEoptusnet.com.au> wrote in message > news:4baa05e4$0$9751$afc38c87(a)news.optusnet.com.au... >> >> "AllYou!" <idaman(a)conversent.net> wrote in message >> news:ZY6dnf6bW5MSaTTWnZ2dnUVZ_jKdnZ2d(a)posted.choiceonecommunications... >>> In news:4ba96073$0$11705$afc38c87(a)news.optusnet.com.au, >>> Peter Webb <webbfamily(a)DIESPAMDIEoptusnet.com.au> mused: >>>> "AllYou!" <idaman(a)conversent.net> wrote in message >>> >>>>> You knew that. And the statement itself proves this with "due >>>>> to its interaction with the lower section of the building". IOW, the >>>>> context was during the time interval of the crash of >>>>> that upper block into the lower support structure. >>>>> >>>> >>>> Perhaps. >>>> >>>> For your information, the statement that was provided is true >>>> when the top section of the building is falling between floors, >>>> and it is also true when the floors collide. >>> >>> But that's not what the statment said. The statement was about the >>> block of floors DURING ITS INTERACTION with the lower structure. No >>> matter how much you lie about it, that's what it was about. >>> >> >> The statement was about when it was "falling". And its true even if you >> interpret this as meaning even during collisions. > > There is no IF, KOOK! It's right there in the statement. And during the > collision, the force normal to the upper block (N) isn't the mg of the > falling block, it's the (d/dt)mv of the falling block. Yes. The total force is (d/dt)mv, this is just the definition of force. > The statement is therefore wrong, and anyone who says it's right is also > wrong. That's you, KOOK! > > Again, if you were to quote exactly what I said that you think is wrong ... >>> All the rest of your bullshit is just a cover for the fact that you >>> thought that statement was made by the NIST, and so you defended it, no >>> matter what it said, and now you can't admit it. >>> >>> >> >> I defended it because its true. >> >> Simple as that. > > Yes, you're a very simplistic thinker. That's why you tried to answer the > question of whether or not there was any resistance to the falling block > by assuming there was none from the outset. LOL! > Perhaps if you were to quote whatever it is I said that you think is wrong ....
From: Peter Webb on 25 Mar 2010 01:10 "Remy McSwain" <Paradis70080(a)gmail.com> wrote in message news:8bSdndtHMvatFzfWnZ2dnUVZ_u2dnZ2d(a)giganews.com... > > "Peter Webb" <webbfamily(a)DIESPAMDIEoptusnet.com.au> wrote in message > news:4baa82e1$0$28464$afc38c87(a)news.optusnet.com.au... >> >> "Remy McSwain" <Paradis70080(a)gmail.com> wrote in message >> news:tKOdnbob24BtiDfWnZ2dnUVZ_oydnZ2d(a)giganews.com... > > [snipped a bunch of lies about not having previously told you where you're > wrong] > > >> I think there is an "upward, normal force deriving fom its interaction >> with the lower part of the building". >> >> I have already told you about 200 times this statement is "absolutely >> correct". > > LOL! Well, as subtle as that lie is, it's a clear indication that you > know you're wrong. THAT isn't the statement you keep claiming is correct. > > THIS, AGAIN, is the statement which you're said, about 200 times, is > "absolutely correct": > > "The only two relevant forces acting on the falling block are > gravity (mg) and an upward normal force (N) due to its interaction > with the lower section of the building." > > Clearly, the N to which he refers is the mg of the upper section. Clearly not. He says there are two forces; if they were the same force there would only be one force. Furtermore, gravity (mg in your terminology) is a downward force, and he says that N is an upward force. He could not possibly be talking about gravitational force (mg). > And just as clearly, he's claiming that it's DURING THE COLLISION. No, he actually says when it is "falling", and doesn't even mention collision in the quote you gave. Not that it matters, the statement is still absolutely correct. > Therefore, taken as a whole, that statement is wrong. DURING THE > COLLISION, the relevant force is F=(d/dt)mv (up to the point of failure of > the support structure). That is always true, and not just for falling buildings. It is the definition of force. > So just as clearly, the reaction (N) of the support structure is to that > force. Not F=mg. > You need to tighten this statement up a bit. The F = (d/dt)mv includes all forces, it is fact the definition of the total force. Which, BTW, is essentially infinite in classical dynamics, as you can see by differentiating the velocity with respect to time in the equations for an inelastic collision. (More correctly, the Force is considered a Dirac delta function, and you can google that as well if you like). > If it were F=mg, then the distance from which that upper block had fallen > prior to the collision would not matter. But it does matter. If it had > fallen from 100 feet, or even 200 feet, the relevant force DURING THE > COLLISION would be much greater. Why? Because the 'v' in (d/dt)mv > would've been much greater because g would've lasted for a much greater > time. That unfortunately does not follow, and nor is it relevant. Force is simply irrelevant to solving the equations of motion for an inelastic collision, as I have pointed out many, many times and is easily confirmed by googling inelastic collision. > > So please stop embarrassing yourself. Admit you were wrong, and move on. > Your pain could be over just that easily. > > > You should say exactly what this "third force" is. F = ma is not saying what the force is, it is a definition of force. If its not gravity, and its not derived from interaction with lower parts of the building, what is it exactly? (Momentum is not a Force).
From: Peter Webb on 25 Mar 2010 01:14
"Remy McSwain" <Paradis70080(a)gmail.com> wrote in message news:u-KdnQG_mruIEzfWnZ2dnUVZ_r6dnZ2d(a)giganews.com... > > "Peter Webb" <webbfamily(a)DIESPAMDIEoptusnet.com.au> wrote in message > news:4baa841d$0$1785$afc38c87(a)news.optusnet.com.au... >> >> "AllYou!" <idaman(a)conversent.net> wrote in message >> news:fqqdnb0isbc-5TfWnZ2dnUVZ_uednZ2d(a)posted.choiceonecommunications... >>> In news:4baa0937$0$1783$afc38c87(a)news.optusnet.com.au, >>> Peter Webb <webbfamily(a)DIESPAMDIEoptusnet.com.au> mused: >>>> "AllYou!" <idaman(a)conversent.net> wrote in message >>>> news:uqCdnaa5sqElYzTWnZ2dnUVZ_o6dnZ2d(a)posted.choiceonecommunications... >>> >>>>> Notice that he's never given his opinion as to what forces he >>>>> thinks were acting upon the upper block DURING THE COLLISION >>>>> with the lower support structure? >>>> >>>> Well, this has been discussed. >>>> >>>> But as I keep pointing out, the forces literally do not enter >>>> the equations for what happens after inelastic collisions (or >>>> elastic ones, for that matter). >>> >>> And as I keep pointing out, the issue that was under debate, and remains >>> so, isn't what happened AFTER the collision. The issue is what were the >>> forces being exerted on the upper block DURING THE COLLISION. >> >> No. >> >> The forces that occur *during* a collision cannot be determined, and do >> not form part of the equations of motion for an inelastic collision. > > The equations for motion for an inelastic collision do not even apply to > the situation of what is occurring DURING THE COLLISION, and so your > continued references to them for that situation is a wrong-headed red > herring. > >> http://en.wikipedia.org/wiki/Inelastic_collision > >> See any mention of forces? No? So why do you think the forces are an >> issue during an inelastic collision? > > See any mention of DURING A COLLISION? NO? See any mention of AFTER A > COLLISION? YES? > > "The formulas for the velocities after a one-dimensional collision are:" > Do you see it now? "AFTER [] COLLISION"? > > So why would you ask me to look at those equations for anything that has > to do with what happens DURING A COLLISION if the site itself says that > those equations are only applicable for the velocities of the masses AFTER > A COLLISION? Are you really that dense? > The formulas show the changes of speed that result from inelastic collisions. Which is what you need to work out how long the building will take to fall. > As I've been explaining to you all along, your confusion stems from the > fact that because this was an inelastic collision, and because you found > those equations on a web site entitled "inelastic collisions", you've > mistakenly concluded that those equations apply to a consideration of the > dynamics of what happens DURING A COLLISION. No, I derived my equations from first principles using conservation of momentum. I didn't and don't need to refer to a web page for this stuff, its really basic physics. > But they do not. As that site clearly indicates, those equations are only > for the purposes of determining the velocities of the masses involved in a > collision, but only AFTER the collision, and not DURING THE COLLISION, > when accelerations and forces are most definitely at work. It gives before and after velocities. Exactly what you need. > > Just admit your mistake, and be done with it. > If you think I have said something incorrect, you should quote my exact words. |