He isn't using high school physics. He is a high school physics teacher with a degree. Nice attempt to conflate the two.
I do not conflate the two.
Most scientific & engineering professions requires that you carefully restrict your public pronouncements to areas that fall within your specific field of expertise. Fortunately for Chandler, teachers do not fall under this restriction.
Chandler's field of expertise is teaching rudimentary physics principles to teenagers. It is not, and never has been, the analysis of collapsing buildings. In this field, he is an absolute amateur. In fact, he is WORSE than an absolute amateur. He is a guy with a little bit of knowledge (not a lot!) who deludes himself into thinking that he knows what he's talking about.
If he were a professional engineer, he would be in grave danger of professional sanction. Not for the fact that "he disagrees with the gov't". But for incompetence.
Re: "using high school physics"…
He is using "high school physics". And he's doing it incompetently, to boot.
A ball falling in a vacuum (untouched by any force other than gravity) is exactly the high school physics problem that he is describing. Unfortunately for Chandler, this is NOT a ball falling in a vacuum. It's a building collapsing. With [edit:
100] several different significant effects that he is overlooking.
Part of every competent analysis is publishing your raw data for public examination. Chandler fails at this. He has repeatedly refused to publish his raw data (position vs. time), and instead publishes only his derived data (velocity vs. time). When pressed, his response is "get the toolkit & generate your own data". This gets an "F" in high school physics.
Part of every competent physics analysis is an "error analysis". Chandler provides none. He'd get a "D" for this in my high school physics class. He'd get an "F" in my freshman engineering classes.
Part of every competent analysis would be an careful assessment of the magnitude of the effect that one was searching for and a comparison of this magnitude to the resolution of your analysis.
In this case, a difficult analysis would require:
1. an analysis of possible failure mechanisms
2. an estimation of the magnitude of the forces that he would expect from the destruction of the north wall associated with each failure mechanism
3. an error analysis on his data showing what sort of resolution his data could provide in terms of resisting force for each proposed failure mechanism.
Performing this analysis with the PROPER failure modes would have shown him that he would not be able to pick out the relatively small resisting forces (compared to the weight of the building) from his acceleration data.
And yet, this is exactly the approach that Chandler ends up using. Except that he performs zero numerical analysis. He merely states that the acceleration is close enough to 'g' to warrant saying that there were "no" resisting forces. He is wrong.
An easier, more informative analysis would be to perform a competent energy balance analysis. He doesn't do this.
Can you point out the "multiple erroneous statements" in Chandler's presentation?
Sure. A brief sampling...
One of the cornerstones of any competent analysis is the correct identification of the various components of the systems that you are modeling. Chandler fails at this. He misidentifies the objects of his analysis. He constantly refers to the north wall as "the building".
A requirement of any competent analysis is researching, understanding & accurately portraying the work of other researchers. Chandler fails at this. He repeatedly misrepresents the statements of NIST engineers.
"this destruction closely resembles a standard controlled demolition." Wrong.
2:30 "if [the building fell at close to gravitational acceleration] were true, this would be a 'smoking gun' for controlled demolition." Wrong.
3:15 "the fact that (the slope of the curve) is straight indicates that it is a uniform acceleration". Wrong. The fact that it is straight is a direct result of the fact that Chandler told the program to find a "linear fit". A linear fit to ANY velocity data (no matter how variable) will result in a constant (i.e., "uniform") acceleration.
3.35 "I focused on just the first few seconds, and the acceleration was essentially 'g'." Wrong. Chandler specifically, intentionally IGNORED the first 0.8 seconds of his data (1.75 seconds of NIST's data), where the acceleration was NOT 'g'. (The data that proves this lie is sitting right behind him on the screen, while he brazenly utters this lie. A lie that he KNOWS is a lie.)
This is Chandler's data, with NIST's data overlaid:
Here is NIST's data:
NIST did a far better job than Chandler at determining when the motion began. Of course, Chandler chooses to ignore when the motion really began.
This is not a bit of trivia. It changes Chandler's fundamental conclusions.
4:30 "9.88 m/sec^2 is closer to "g" than 9.8 m/sec^2". (g ≈ 9.81 m/sec^2)
4:35 NIST generated their 5.4 seconds in order to match their computer model. (NIST is explicitly clear about how they got 5.4 seconds, as shown in Fig 12-75, pg 601 of NCSTAR1-9 (vole 2, pdf pg 263). They tied it to explicit movements in the motion of the building. This is simply Chandler's "gee, I can't figure out where NIST got it's start point. It must be because they're frauds" nonsense.)
Mistake: "Sunder's statements are a lie. All it takes to expose the lie is someone with a physics background … to expose the lie." It takes someone with a structural engineering background to understand & competently analyze the data & to draw knowledgeable, informed, competent conclusions. A high school physics teacher has none of the necessary experience, training or knowledge.
That's just a few of the numerous errors in the first video. Do you want me to go thru the second one too?
tom
PS. Why do you walk away from discussions once your assertions have been shown to be baseless, rather than addressing the issues presented to you like a person of integrity, a person honestly searching for the truth, would do?
