insane_alien

an example of a hydrocarbon fire melting steel is an oxy-acetylene torch. acetylene is a hydrocarbon. when the torch is ignite the hydrocarbon is on fire. 2000*C flame. used for welding and cutting steel.

actually, it was more a case of way too much time, a liberal application of booze and boredom.

The first thing i notice when watching that 'documentary' is the fact that they use opinions of laymen on the fact that there was an explosion. there are many things people would describe as an explosion but are not actual explosions. such as collapses. it has been used to describe rockfalls and when icebergs break off an ice shelf. and unless you believe that it's a secret government demolition team breaking off icebergs then you'll know that that just isn't true. <edit> the video won't play past 10 minutes.

WARNING: huge mega post. may cause anneurisms in conspiracy nuts. Righty ho! since tree99 is being anal about this i might as well do it. *NOTE: some quotes were edited for formatting reasons and to aid clarity. the content was not changed(well, appart from a snip which is explained) uh oh! no sources or even mention of how this was calculated! most people would just say 'he timed it from a video' and be fine about it. but tree is being pernickity about it so i will too. did he use a stop watch? did he play it frame by frame? what frame rate was it recorded in as this can vary from what its displayed at? did he use measurements from multiple cameras to check his results? could he see the ground from the angle? i want to know! this i have no problem with. all true' date=' all verifiable(though still no sources in the article) and no inferences. as anyone who's done a basic science class should have drilled into them by their teacher. yeah the media reported a model. doesn't mean thats what they were given. if the people incharge had a model then there would have been no investigation. since there is then we can be sure that they are checking out their hypotheses. at the time the plan was, get something out there. let the public know we're working on it. ass for the questions after Cheney's quote, the pilots were highly trained, at flying planes, not so highly trained at counter terrorist operations. after they had control there wasn't much else to do other than point the planes in the right direction. also referring to this as 'the official conspiracy theory' thats just bad science. its like claiming newton was covering up general relativity when he published his laws of gravity. i've clipped the pictures. if you want to see them go read the pdf. i have an issue with the title of this section. the collapse was NOT symmetrical. one end started falling before the others. look on youtube and you'll see plenty of videos of it. as for the proposed method of measuring the time taken, its very inaccurate both because of human involvement and the lack of knowledge of the initial frame rate. in tv the cameras record at a different framerate than they are broadcast. this can introduce a bit of error as well. also, it is unknown if the ground level can be seen in the videos he used. if it can't then the time cannot be taken as accurate since we don't know if he stopped timing when he couldn't see it anymore or if he used a fudge factor. either way would be wrong. a personal opinion. he is not a demolition expert or someone who knows ho buildings fail. this cannot be taken as scientific evidence just as it wouldn't be used as evidence in a court of law. again, from my previous comments we cannot tell if 6.5s is accurate. the fact that it fell slower than free fall is an example of physics working. if it fell at or faster than freefall acceleration then i would be curious. no mention of the failure mode. it would fall differently if the major failure was at the top or bottom. it would fall faster if it failed at the bottom rather than the top. from watching the videos it seems that the building broke somewhere near the bottom as the main chunk of the building collapses at the same time. if it collapses from near the top it would look more like the towers. oh goody. some hard science at last. it'll either be right or wrong. lets see what we get. what? i was promised momentum not a poncy y=0.5gt^2. also, if there were explosives 1/ we would hear and see them 2/ explosives in demolitions don't move material out of the way they just weaken the structure. gravity does the hard work. so, we have a building that is damaged and structurally weakened by fire. it fell almost straight down. doesn't seem impossible to me. also, have you seen a building primed with explosives? there is det cord EVERYWHERE i'm sure workers would have notice clambering through a spider web of explosives. and it didn't collapse symmetrically. this guy said we would get a momentum analysis. not one bit of momentum calculations there. low probability does not mean it can't happen. bad use of probability got to jail do not pass go do not collect £200. because cluster charges are NOTICABLE! THEY ARE VERY VERY LOUD! they also explode. i didn't see any explosions. someone would have heard the sharp whip like crack, the large puffs of smoke and debris(since it presumably wasn't shielded) before it fell. it would even be visible on the videos. okay, look this is going way off topic. and i'm not even half way through. i'm going to fast forward to the bits related to molten metal. so it goes from 'yellow and orange material' to 'metal flowing'. this ladies and gentleman is called an ASSUMPTION a leap of faith if you will. he is assuming that the yellow orange material is glowing liquid metal. the substance does indeed behave like a liquid. it cannot be denied. lets look at the candidates, 1/ burning jet fuel is liquid and yellow/orange. lots of fuel was rather violently deposited in the towers leaveing a big gaping hole for it to flow out of. 2/ the fire reached an intensity such that the structure began to melt. this resulted in molten steel flowing out of the building. 3/ other burning liquid substances such as platics 4/ other glowing liquids such as glass. since we are primarily looking at steel as this is your area of contention we will note what is missing. sparks. have you ever watched steel being poured in a refinery? sparks shoot everywhere as it ignites these are missing. therefore it cannot have been steel. as 1/ would be the most abundant it is probable that it was indeed 1/ could be paper ash. it was an office building. could possibly be a magnesium alloy. could also cause the white ash. there was more than one combustible material present i'm sure, given enough time, i could walk into an office and find something that burns brightly with white smoke. ooo missing the burning jet fuel again. what do you think it all burnt up within seconds? ignoring possibilities. not good science. also, similarity does not mean they are the same. i look like my dad. but that does not mean that i am my dad(that would be very very weird and violate causality or something.) same with reactions. no one is contending that the steel did melt. it didn't need to melt only needed to soften which the temperature were more than capable of doing. again this assumes that it was a metal. there is no evidence for that. and it goes on to explain why it wasn't aluminum because of their experiments , because a garage is soo much like your standard kerosene soaked inferno. that does actually render the experiments themselves useless. so, i'll conclude. the guy blatantly ignores possibilities doesn't provide any hard evidence and in general doesn't follow the scientific principles that well. sorry this metric assload of post but it was at tree99's request.

to revise? a lot of lecturers do not hand out notes and not everything they tell you is in the notes if they do hand notes out.

mine too. that would be awesome. just keep applying the logic and your balance will increase geometrically.

fine i'll analyse it. come back tomorrow i'll have a pretty in depth one ready.

well, if you had bothered to do a simple search on these forums you would see that we have answered it ad nauseum

oh right, so a scientist whose field is in fusion is going to pretty well informed about structural engineering and the chemical aspects of it yeah. of course it all makes sense now. i only spent 15 minutes on it cause i'm tired and couldn't really be arsed to be frank. its the same old crap again and again.

why does that begin with talking about fusion? really. come on. anyway, is it so hard to imagine that what was falling out the building was burning jet fuel. there was only around 10000 gallons up there per building. and is it also so hard to imagine that there would be suitable conditions for at least localised hot spots especially considering the amount of combustibles in the building. not to mention the things that don't usually burn. like metals. the conditions would have been good for a good number of things to burn. and then there are thermite reactions. not only between aluminium and ironoxide but other things like copper. there are a lot of things there that could produce very high temps. especially with the winds and ability to draw air up through the stair wells and lift shafts. these would further increase the temperature of the fires.

hydrocarbons have different maximum temperatures for different conditions. it is perfectly possible to get a kerosene fire up to 2500*C y'know, one of these days i'm gonna go get a steel drum, some rubble and a bunch of kerosene and prove it.

... his mum? sorry, had to be said. on a more serious note, what does this have to do with a black hole at the centre of the universe? not that there even is a centre

it could have been. it could also have been molten plastic that was smoldering there are a plethora of substances it could have been including steel as after the collapse the debris would have made very good insulation.

appart from the strong force being an attractive force it also weakens as the distance gets shorter. the weak force doesn't have the range or ability to do anything

ah that makes sense. thanks. although, in my experience i would be quicker drawing the graphics out by hand than using IE

i don't think any kilowatts are present. you might choose to measure the energy in kilowatt·hrs.

well, he was a lot clearer in his wording than you are. seriously my mind is tied in knots trying to figure out what you said.

oh you mean the daisy cutter. yeah. thats a normal bomb. 70MPa over pressure according to wikipedia and its references. http://en.wikipedia.org/wiki/BLU-82 most definitely not a vacuum device.

its not zero pressure. its just lower than atmospheric. it works in the same way low pressure systems in the weather work. hot air rises. the big fire ball is hot, it rises fast and therefore pulls in a lot of air behind it. implosions like you are imagining don't really exist. <Additional> i looked up BIG BLU, its very much an explosive device. it just penetrates 200ft of 5000psi concrete first.

and i answered. the designers didn't account for an internal attack. the most likely vector for a plane hitting the towers was when it was coming into land. when its getting low on fuel. if they were low on fuel then the fire wouldn't have been as fierce and the building would have survived. engineering it to withstand a fully fuelled aircraft impact would have been over engineering. it may be reasonable for a nuclear power plant but not for a commerce building.

i'm also under the impression that the speed you get is dependant solely on connection speed (at least with modern processors unless your running every bit of software you own at once on an infected vista machine)

heh great minds think alike. hadn't seen that one before.

thanks alan but i think we'll wait for my latest exam results on that one. i'm pretty sure i've failed business management practices. and possibly maths if only because i can't remember sitting it(though i know i was there). and to expand on the whatever thing, theories and hypotheses are very important parts of science. a hypothesis is pretty much speculation and hasn't underwent very much investigation. a theory on the other hand has been proven correct(or at least better than current models) through experimentation and observations. very different things.

HA! never even thought of comparing it to the titanic. i wonder what the conspiracy sites would have said then if the internet was around then. probably the same as this. " it was made of STEEL ice can't break STEEL!" i can also imagine them showing an experiment with an ice cube and a steel tin to 'prove' that ice can't tear it.

i think the e is supposed to be an a.