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9/11 Experiments: Newton vs. NIST

Great video!

I am sticking with Newton. NIST and its nanotechnology experts are wrong.

I agree

The laws of physics are constant. There is no argument but the average person doesn't look at it that way. When it comes to 9/11 they don't want to believe it was an inside job therefore they choose to believe the "Official Story". I don't care what you tell them they are in a state of denial. The truth is too horrible to handle for them. In my case when I found out it 9/11 was an inside job I was in a state of shock for some time. I simply did not want to believe the truth about 9/11 but I had too. I could not deny what I saw no matter how much it hurt. Lets face it, that is our biggest problem convincing the average person. No one wants to believe that their Government is run by a bunch of thugs. I guess eventually people will come around. I just hope it isn't too late when that happens. Time is not on our side. By the way I was listening to Alex Jones yesterday and he interviewed Jesse Ventura. Jesse will continue with his TV program this coming year so in my opinion that is good news.

Yes it was good

but it can be a little confusing.

I like to point out the relative time difference between absolute free fall, and the actual fall time, which is about three seconds.

Thus, in absolute free fall, we have an object falling through nothing at all (except mere air) and in the case of the twin towers' destruction, supposedly crashing down in a pancake type collapse, or, a crush down, crush up, through the path of maximal resistence, whereby, the only available space of time, for all crushing and breakage to occur, resides in the difference between a fall through nothing, and a fall through something, or a difference, of approx 3 seconds.

So if, in the case of the north tower, we spread out those three seconds, across 95 floors of "breakage", then we immediately recognize that there's a negligable difference, between free fall, and the actual timed destruction, which occured through the path of maximal resistence. This would amount to an action/reaction of breakage occuring across the entire remaining length of structure taking place at about - the speed of sound.

The official story and the NIST theory of global progressive collapse, amounts to what I like to call "The Foot of God Hypothesis". Absent the use of explosives, it's absurd.

Someday everyone will come to understand this.

So the key, for me, resides in the time of destruction relative to absolute free fall, making the twin towers sheer height, the best proof of CD.

Illustration:
Something vs. Nothing

So, if NIST and Bazant are to be believed, this is what the action/reaction of crush down, crush up would HAVE to look like..

A) 110 story high rise steel structure with impact damage and fire at one level of the building

ONE) Crush down
TWO)
THREE) Crush up

B) Pile of rubble.

Take a look at the second hand of a clock or watch, and note the space of time that is three seconds. One two three.

The buildings could not have progressively "collapsed" and got crushed, floor on floor, from top to bottom, in three seconds.

Can anyone clap their hands 95 times in 3 seconds?

Why I never get voted up

more for this proof is always baffling to me.

Edit: Out of fairness and just to be clear, I forgot to add that absolute free fall in nothing but air, from the height of the twin towers, is 10 seconds (9.2 in a vacuum), and the recorded time of destruction of the buildings - about 13 seconds.

P.S. Why DON'T we have a physics paper published anywhere, why is that again..?!

Not so confusing

with repeated viewings. In fact, when I finally got it, I realized Jon simplified things as much as anyone possibly could.

Thank you, Jon, for inspiring me and giving me a few more ways to argue the collapse of the towers in simple physics terms.

This is no doubt your best video yet.

Measuring deceleration.

Good video.

The only concern I have in regards to the WTC collapses is where is it best to look for deceleration. In the case of WTC1, Chandler and others looked at the roofline. However, the initial area of impact was at the 98th floor, the roofline is roughly 145 feet higher. The jolt/shock will attenuate the further one goes from the area of impact. It also depends on how rigid the material is. Attenuation will be be less in a rigid compared to a non-rigid structure.

Gregory Jenkins made this point in his article, "Interpreting the Boeing-767 Deceleration During Impact with the WTC Tower: Center of Mass Versus Tail-end Motion, and Instantaneous Versus Average Velocity", published at the Journal of 9/11 Studies. Morgan Reynolds and others were arguing that no real planes impacted the World Trade Towers because there was no measurable deceleration upon impact. Jenkins argued that if one measured from the tail-end it would not necessarily be expected.

"However, this miniscule deceleration does not represent the deceleration of the entire airplane, only the tail end. The center of mass represents the motion of the entire airplane. Since the front of the aircraft decelerates faster than the tail due to impact, the center of mass shifts towards the tail end. Therefore, the center of mass of the plane travels less distance than the tail."

He also analyzed the impact+of+an+F-4+Phantom+Jet into a concrete wall. He concluded, "Normalized F-4 tail-end velocity shows no change within error before or during impact." By measuring from the roofline we are essentially measuring from the tail-end.

However, the World Trade Towers were made of materials far more rigid than an airplane and spandrels were used to connect the perimeter columns at each floor level.

- Would it be possible to measure for deceleration at a lower point than the roofline?

- Are there any experiments, data or calculations to show how much the jolt will attenuate by the time it reaches the roofline?

Back to your regular programing....

No loss of momentum

That's the point I think, is that it's hard to FIND any deceleration, which violates Newtons three laws of motion.

The buildings blew up, and out, from the top down, the explosively ejected building material "wave" of debris, moving down, absent any appreciable loss of momentum, all the way to the ground, and as I pointed out with the "something vs. nothing" thought experiment, there's only maybe three seconds within which any deceleration can have occured, relative to absolute free fall.

The "problem" is with the notion that what was observed was a "collapse", since that's not what actually occured, in reality.

Absent the use of explosives, the Zelikow public myth about what happened there, is absurd, right on the face of it.

The truth cannot be twisted or confused in this regard.

It's obvious, self evident.

I think the 911 Truth Movement Needs a Physics Sim Site

I posted this earlier in another thread. I guess I must be the only eone who is fascinated with the physics sim software that is become ever more sophisticated.

A large community of games programmers incorportate this software in the video games they create. Isn't there some way the 911 Truth Movement could organize some games programmers to do some physics sims that illustrate the problems we keep talking about?

http://singularityhub.com/2010/07/22/teaser-trailer-for-a-3d-physics-eng...

A decent physics simulation would get much internet attention if it were flexible enough to allow some of the parameters of the building construction or some of the conditions of the simulation to be adjusted by users. Of course, you could do a presentation on the Law of Conservation of Momentum using lots of different examples besides Tower mock-ups.

I always imagined that a bang-up, interactive physics sim of the Towers and Building 7 would have the capability to go viral as users try their best tweaks to get the buildings to collapse the way they actually did. And perhaps some elaborate tweaking COULD get the buildings to collapse like they did. But everyone would be able to see just how unrealistic the tweaks would have to be - probably about as unrealistic as NIST's computer software had to be in order to mimic Building 7's destruction.

You couldn't "prove" anything using software, but you could quickly get ideas across and do it in an easy, entertaining way.

And then stick it in the main town center

of "Second Life", so that millions can come there and see it in person (whether a member of Second Life or not), along with a University style lecture and series of presentations.

A virtual physics sim, now wouldn't that be something.

And some day we'll see a physics paper published on this, which will never be debunked, ever, and then it will become accepted in the global scientific community, that 9/11 was indeed an "inside job", at least in terms of the mechanics of destruction of building 7 and the twin towers, which did not "collapse" as a result of the plane impacts.

We've got to start thinking both short and longgggg term, to make a mark on history with this evidence, I think you've got the right idea.

If it were an interactive simulation

Normally, to do a physics simulation of Building 7, it would take 50 - 75 man-years of programming effort. But if you do a simplified version using current physics sim software, then the task is made much easier. In fact, there so much controversy surrounding the building collapses that I have trouble explaining to myself why it is that NO games/physics programmers are showing off their skills by doing some 911-based demonstrations.

It would have very good potential of going viral all over the world!

I can imagine a simple game-themed physics simulation of Building 7 where players have to reduce the strength of steel, increase the temperature of fires to abnormally high levels, eliminate or weaken connectors... whatever concoction of tweaks they think might allow the buildings to fall the way they did.

http://www.lagoatechnologies.com/

How can you look at those stunning physics renderings and NOT think about their potential for use in destroying the official hogwash? You would not need to build a gargantuan model just to make it clear to "players" that the buildings could not have collapsed without explosives. And, of course, players could place some explosives in the the building if they wanted to. I mean, after they've tried everything else, they would HAVE to resort to explosives in order to get the physics sim to reasonably approximate what was actually seen in NY that day.

It's a BRILLIANT idea Dearth, Big Time!

And it could take on any number of manifestations on the Internet, as more and more people get hold of it, and start working with it.

But it would HAVE to include, and even be centered around the Twin Towers, while including, of course, Building 7.

I don't see how anyone can crush the building with the top part, according to ANY collapse initiation scenario, in 3 or 4 seconds, it's just not possible, there's no time for the crushing dynamic, to take place.

But it would be really neat, like I said, if it could be modelled in 3D virtual reality as well, for people to explore and interact with, and the physics programs are also there in Second Life, upon which a sim could be made.

But at the very least, for people to be able to even SEE the simulations, from a number of angles and perspectives, would shed more light on the issue in a very big way, you're right.

We also need, our movement, to somehow get some physics papers published in recognized physics and engineering science journals, at the same time, to propell the issue into the global academic and scientific sphere.. while openly INVITING any and all attempts at rebuttal.

And then the real debate finally begins at last.. as we move from

ridculed, through violently opposed, to:

accepted, as self evident (no matter what the implications may be for the US and global history)

I sent an email to John Hatton...

...author of "Advanced Game Programming" which I found at the discussion board, http://www.gamedev.net/

I had seen a post where Mr. Hattan was described as a published expert in game programming physics.

From http://www.amazon.com/Advanced-Game-Programming-GameDev-net-Collection/d...,

"John Hattan has been working steadily in the casual game-space since the TRS-80 days and professionally since 1990. After seeing his small-format games turned down for what turned out to be Tandy's last PC release, he took them independent, eventually releasing them as several discount game-packs through a couple of publishers. The packs are actually still available on store-shelves, although you'll need a keen eye to find them nowadays. He continues to work in the casual game-space as an independent developer, largely working on games in Flash for his website, The Code Zone (www.thecodezone.com). His current scheme is to distribute his games virally on various web-portals and widget platforms. In addition, John writes weekly product reviews and blogs (over ten years old) for www.gamedev.net from his home office where he lives with his wife and daughter in their home in the woods near Lake Grapevine in Texas."

I kind of wish Steve Jones or David Chandler would get involved in something like this - along with the support of the entire 911 Truth Community. No doubt we would have lots of trouble fundingmore than a small, inadequate project, but perhaps there are some games programmers out there who would like to make a name for themselves by doing a lot of the programming for free. I'm sure this thing would go viral.

It seems such a shame to waste the resource of steadily advancing physics sim software.

At any rate, please send a similar email to other game programmers with physics sim knowledge. Maybe we'll get a couple of bites.

-----------------------------------------------------------------------------------------------------------------------------------------------------------

Dear John Hattan,

I'm writing to you because you've written a book on games physics programming and you would probably have some good suggestions for us. Some of us are wondering what it would cost to do fairly simple (but scientifically reasonable) interactive simulations of the building collapses in NY on 9-11-2001.

I imagine an interactive site that illustrates the conservation of momentum using sophisticated physics software such as this (soon-to-be) release:

http://www.lagoatechnologies.com/

If you are not acquainted with the controversy surrounding the building collapses, high school physics teacher, David Chandler, has done some interesting video analysis here:

http://www.youtube.com/watch?v=rP9Qp5QWRMQ

...and has written a short paper:

http://www.journalof911studies.com/volume/2010/ChandlerDownwardAccelerat...

(I like to call it "The High School Physics Paper That Ate New York").

David Chandler is one of many professors, engineers and scientists who have pointed out the violations of physics in the collapses over the years.

There has never been any official explanation for why the Towers and Building 7 fell at freefall acceleration. And, of course, this freefall acceleration conundrum bothers people the world over. The National Institute of Standards and Technology (NIST) did its own computer physics simulation of the collapse of Building 7 but it refuses to release any source code or any of the parameters which it used.

It was through their simulation that NIST declared in its Final Report that Building 7 was the first steel-framed skyscraper ever to collapse solely due to ordinary office fires. And NIST actually DID admit to 2 1/2 seconds of absolute freefall acceleration through the path of greatest resistance. "Impossible!", many trained professionals declare (see http://www.ae911truth.org/. Architect Richard Gage's presentation "911: Blueprint for Truth" is the best. Watch it there for free).

Normally, to do a physics simulation of Building 7 or one of the Towers, it would take 50-100 man-years of programming effort. But if one were to do a simplified version using current physics sim software, then the task would be much easier. Also, we are not trying to PROVE anything using software; we want to illustrate the violation of conservation of momentum and other aspects of Newton's Laws pertaining to 911 in an easy, interesting, and reasonably accurate way. It's frustrating to be consistently labelled a "nutjob" for merely pointing out well-known Laws of Nature.

Suppose we wanted to build a simplified simulation of Building 7 or one of the Towers in which some of the collapse assumptions and parameters can be adjusted by users. Certainly such a thing wouldn't be more expensive than a game, right?

What would such a project cost in your guestimation? What kinds of issues would you have to take into consideration when preparing a proposal to do such a project?

Sincerely,

Carl Nelson

incomplete source

Dearth, NIST did release some code and parameters (see my post below), but they left out the presumably important 'connection models'. But the ANSYS engine itself is entirely closed source, and if Lagoa is commercial it probably is too - however there are open source engines available.

By the way, do you know if the best videos of the NIST simulation are on it's home page? The few I can find are very bad quality.

Did NIST pull their simulation down?

I haven't found NIST's wtc7 simulation quite some time now. I am stating to think they pulled it. A search for WTC7 Simulation at nist.gov does not find it. Why would they take it down? It hasn't been even 2 years since it's release. Are they THAT ashamed of it? I must admit, it is so bad that it becomes another tool for us.

peace all

dtg

excellent video Jon, BRAVO!! keep 'em comin..

oh yeah

They were there a few months ago, I think the link was somewhere on this page
http://wtc.nist.gov/
and it went here
http://www.nist.gov/public_affairs/releases/wtc_videos/wtc_videos.html

But now that page says:

"Page Not Available
The NIST Web site has been redesigned and the page you requested is not available at this time..."

I managed to download the four videos that were there a while ago (wasn't made particularly easy as I remember), and I just uploaded them here, take a look.

http://nist-wtc7.googlecode.com/hg/videos/12th-Floor_Fire.wmv
http://nist-wtc7.googlecode.com/hg/videos/CU%20animation.flv
http://nist-wtc7.googlecode.com/hg/videos/Collapse_Initiation.wmv
http://nist-wtc7.googlecode.com/hg/videos/WTC7_Debris_Impact_Damage.wmv

Unfortunately they are in the silly 'flv' and 'wmv' formats but most computers should play them ok.

Anyway it doesn't look like freefall acceleration to me, but in their FAQ here NIST say

"The analyses of the video (both the estimation of the instant the roofline began to descend and the calculated velocity and acceleration of a point on the roofline) revealed three distinct stages characterizing the 5.4 seconds of collapse:

* Stage 1 (0 to 1.75 seconds): acceleration less than that of gravity (i.e., slower than free fall).
* Stage 2 (1.75 to 4.0 seconds): gravitational acceleration (free fall)
* Stage 3 (4.0 to 5.4 seconds): decreased acceleration, again less than that of gravity"

I don't see this in the videos above. Am I missing something?

Edit:Missed one, the 'no debris impact damage' video.

http://nist-wtc7.googlecode.com/hg/videos/WTC7_No_Debris_Impact_Damage.wmv

Got it, Thank you ID

That was a big help. I used to just have the links at NIST and now none work of course. I saved the files for my own edification too. Maybe we could share them with Dwain Deets for his new site. Having the computer sim and the real thing running together side by side seems like it would be quite an effective tool. thanks again.

dtg

More NIST archives

http://preview.tinyurl.com/2bf5fx2
(site is very slow to load... working on that)

maybe some combination

of these?

http://code.google.com/p/nist-wtc7
http://armorgames.com/play/4142/demolition-city

The Lagoa demo is graphically impressive, but maybe it could be criticised for accuracy (compared to say ANSYS which NIST used). However I'm sure 'real world' settings would rule out freefall. The original NIST fire/gravity simulations ran from days to months I think, but I would imagine the latest physics engines support processing on the now common GPUs (as opposed to CPUs), which are potentially much faster at that sort of thing.

Did the NIST simulation experience freefall anyway?

I personally find closed source simulators a bit unscientific in the first place, and something like Jon's demonstrations more compelling, so I was amused by a youtube reply in response to another video of his to the effect of 'real experiments aren't complex enough you need to use software like NIST did which i have heard was very complex'.

Well, I had looked at Jonathan Cole's youtube at the start

of this thread. And, even though he was being as clear and simple as he possibly could be, I could tell that uninitiated viewers would not sit through the thing. Only people who already understood the physics violations would watch it with any interest - just to see how well Mr. Cole presented the concepts.

So, how do you get the unwashed multitudes to grok this stuff and remember it as important? How do you viralize this thing? And how do you condense this information into byte-sized pieces suitable for viral replication on news programs or other websites?

People learn and understand MOST effectively through visual examples. And when they can get their fingers into something and play around with it a little, it's all for the better. A set of physics simulations of the building collapses in NY would eliminate the necessity of having to blow a lot of hot air into blank faces. You know what I mean?

Actually, author David H. Eberly would probably be a really great guy to chat with about the whole thing.

http://www.amazon.com/Game-Physics-Second-David-Eberly/dp/0123749034/ref...

"This comprehensive introduction to the field of game physics will be invaluable to anyone interested in the increasingly more important aspect of video game production, namely, striving to achieve realism. Drawing from areas such as robotics, dynamic simulation, mathematical modeling, and control theory, this book succeeds in presenting the material in a concise and cohesive way. As a matter of fact, it can be recommended not only to video game professionals but also to students and practitioners of the above-mentioned disciplines." -Pål-Kristian Engstad, Senior Software Engineer, Naughty Dog, Inc.

"Increases in processor power now make it feasible to run complex physical simulations in real time, which greatly increases their practical importance. Thus there is an increasing need for books like David Eberly's Game Physics that can give graphics programmers a grounding in the physical principles that underlie realistic computer animation." - W.Lewis Johnson --Physics Today

"Product Description
Create physically realistic 3D Graphics environments with this introduction to the ideas and techniques behind the process. Author David H. Eberly includes simulations to introduce the key problems involved and then gradually reveals the mathematical and physical concepts needed to solve them. He then describes all the algorithmic foundations and uses code examples and working source code to show how they are implemented, culminating in a large collection of physical simulations. The book tackles the complex, challenging issues that other books avoid, including Lagrangian dynamics, rigid body dynamics, impulse methods, resting contact, linear complementarity problems, deformable bodies, mass-spring systems, friction, numerical solution of differential equations, numerical stability and its relationship to physical stability, and Verlet integration methods. This book even describes when real physics isn't necessary - and hacked physics will do."

Does anyone know Jim Hoffman? Maybe Hoffman could tell us what would be required to do a physics sim site designed to entertain and educate viewers/players about 911.

Ideas

Dearth, I may be able to help with the implementation of such a project. Could you contact me through my profile page at blogger .. it might be useful to discuss some possibilities.

Now that's a great

Now that's a great idea...call it the Great American Physics Challenge

And then there is the obvious: explosion at :45

I am not a physicist, not by a long shot, but I do understand the principles of physics and how they are completely dismissed in the NIST accounts of 9/11. Political reality trumps facts every time in their world, apparently.

Even so, how in the world do those people reconcile the massive explosion seen at :45 on this video, with their "collapse due to fire" explanation? Though it is not at the initiation of the destruction, I question what explosive material could there still be after the fires were supposedly already so intense and "globally heating" as to render even the massive steel structure as good as rubber? An explosion under those circumstances is redundant and an incredibly damning tell it seems, and I am surprised I don't recall anyone ever pointing it out though I have spent years poring over 9/11 videos, books and internet analysis.

But perhaps a physicist will enlighten me as to why this explosion is meaningless. I hate being ignorant on crucial matters. If it IS significant on the other hand, more needs to be made of it, because to the non-scientists among us (and let's face it: most people will not believe there was a cover-up because they refuse to see the evidence laid bare by science), it sure looks like more than a smoking gun. It looks like one of the guns in the process of being fired.

In response to Tanabear's question

The frequency of the perimeter wall and the shock pulse are the parameters which would have determined how much attenuation, if any, would have occurred.

Shock transmissibility is a function of the natural frequency of the impacted objects to the frequency of the pulse. Above a ratio of 0.5 there is no attenuation, with values below this threshold having increasing attenuation.

The natural frequency of a 12 story perimeter wall of the upper section of WTC 1 was about 4.5 Hz. The frequency of the pulse would likely be in the 1 to 10 Hz range due to deflections. So it is very unlikely that the shock would not be transmitted to the roofline, if there had been an impulse. It really doesn't look like there was. It seems the legs were being taken out from under the structure in a timed fashion on the way down and that is why there was no jolt.

Reply:

Yes, I agree the World Trade Towers were destroyed top to bottom via demolition charges. That fact is obvious from watching the videos alone. I was just making sure we had all our ducks in a row.

Now for clarification on your above post. How did you determine the natural frequency of the 12 story perimeter wall? I assume this was extrapolated from the natural frequency of steel plus the mass of the perimeter columns?

What is frequency of the pulse? Is this suppose to be the frequency generated by the impact of the upper and lower block?

So if the Natural Frequency is (4.5 Hertz) / Frequency of the Pulse (9 Hertz or less) >= 0.5 there will be no attenuation? Can you explain why this is the case? I would have assumed that there would always be some sort of attenuation based on the object the shock is being transmitted through and the distance.

Thanks...

Look up a shock transmissibility curve

and you will see that shock is not attenuated above a ratio of 0.5 for natural frequency/shock pulse frequency, and when the ratio is above 0.5 it can be amplified. The reason is that the shock is not isolated above a ratio of 0.5. The isolation/lack of isolation has something to do with wavelength and elastic waves. Some might think damping would play a part but damping has little effect on the initial shock response. Damping is 5% of critical for bolted joints and about 1% for welded joints. The perimeter column structure was bolted joints between column sections and spandrel sections and the spandrels were welded to the columns.

I calculated the natural frequency of the perimeter wall for the upper 12 stories of WTC 1 using the classic equation 3.13 x square root of K/W. Where K is the axial spring constant of the perimeter wall, and W is the weight of the columns plus half of the floor weight outside of the core. The spring constant is found using the equation K = AE/L where A is cross sectional area, E is modulus of elasticity of steel, and L is the length of the column. The calculation was done for eight foot sections of perimeter columns only plus 52 inch sections of columns and 1.00 inch thick spandrels at each story which were then added as series springs and the same done for 12 stories.

Frequency is the reciprocal of the period. Since a shock pulse is half a cycle, its period is 2 x duration and the frequency is found by the reciprocal of 2 x the duration of the pulse. For example, if the duration of the pulse is 50 milliseconds then 1/(2 x .050) = 10 Hz.

If the duration of the pulse is less than 50 milliseconds there will be some attenuation, but it probably would not have been a lot lower due to relatively high deflection at the point of impact in a structure like the perimeter walls. Additionally, the apparent natural frequency of the perimeter wall in an impact would probably have been somewhat higher than 4.5 Hz due to much of the floor mass not participating fully. If the weight of the floors is not used the axial natural frequency of the upper 12 stories of the perimeter walls is about 16 Hz. In this case the shock pulse duration could be 15 milliseconds and no isolation or attenuation would occur. With a 16 Hz natural frequency, even if the shock pulse was a short duration of 11 milliseconds (which is generally assumed for fairly rigid systems) the ratio would be about 0.35 and the attenuation would have only been about 40 to 50%.

I have also thought it would be a good idea to measure points down near the impact, if possible, as that would nail it down in no uncertain terms. However, while I would be willing to say some level of attenuation would probably occur from impact to roofline, I think it can be confidently stated that it would not be nearly enough to prevent a velocity loss due to the deceleration necesary for the required load amplification to continue a natural collapse from being observed, such as what is seen in the roofline measurements of all of the Verinage demolitions.

Reply II

I need a primer on shock transmissibility. I'm not real clear on all the physics behind it. I do like to keep up on all relevant 9/11 info regardless of whether it is technical or not. I might have to apply myself somewhat in this regard.

Yes, I too believed that measuring at a lower point than the roofline would be helpful. It would probably be difficult to track an area for an extended period of time as much of the view is obscured by the smoke, especially once the collapse begins. However, to refute Bazant which just need to show there was no deceleration after a drop of 3.7 meters(12 feet).

Do you know the distance from the roofline to the impact point in some of the Verinage demolitions? And in those demolitions is it possible to measure for decleration at a location closer to the impact point and compare that to the deceleration measured from the roofline? It seems that this might be a good way to determine the attenuation of the jolt.

The upper sections of most of the Verinage demolitions

were approximately 6 stories tall.

Another superb physics lesson.

Thank you, Jon, for another superb physics lesson. When David Chandler said the falling block was exerting less force than when it was stationary, it seemed counter-intuitive to me. After seeing your experiments, I now understand and can see that it is in fact obvious. Keep up the great work!

Informative!

Thank you

The key term here is uniformity

Only a controlled demolition would include uniformity in the destruction of the mass so that these entire structures would completely collapse. Three in one day ? All completely collapsing ? All the explosives in the dust helps settle that issue, now if someone in a law enforcement capacity would actually seek indictments...

Jon, great little piece. It

Jon, great little piece. It could use a slower delivery style though. We must always remember that while we understand these concepts, many non technical people don't.

We need more videos like

We need more videos like this. Somebody should send this to Mr. Assange. He could use a primer in science, logic and deductive reasoning.

Legal Challenge to NIST?

Where are Lawyers for 9-11 truth?, surely NIST are culpable of serious offences. Why not a fund to call NIST to account in a court of Law?

re Chandler's name attached to this

ok..... I had trouble following this video...... I notice that Chandler's name is attached to this video.... but this is not as clear and easy to follow as Chandler's own videos.......