Richard Gage Blueprint for Truth Rebuttals on YouTube by Chris Mohr

[ozeco41]

Originally Posted by sheeplesnshills View Post
Well again not quite true. If fired from a high enough altitude and at sufficient speed the cannon ball would go into a stable orbit. It would be in freefall but it would never get any nearer the ground.

Er, well, add "flat earth" to the list of assumptions, or we'll also have to cope with the fact that ballistic trajectories are ellipse arcs instead of parabolas ....

Will you big boys please go back to your own classroom. We are trying to teach Grade 1 here.

 

[Christopher7]

And your claim, C7, "everything within the system is falling at free fall acceleration and cannot cause any other part of the system to alter its rate of decent" is clearly wrong.

Ozeco is right, and you are in fact totally wrong on just about everything

No, he is dead wrong and I don't have time to answer every point in every post.

Chris Mohr's statement that started this :

And freefall is not always straight down.If I shoot a cannonball, it is traveling mostly horizontally but still dropping at freefall acceleration (minus air resistance). You continue to ignore Tri's photos which show Building 7 leaning just as it is beginning to collapse.

Chris is inferring that WTC 7 was falling to the side during the period of free fall acceleration.

Is that correct Chris? If not, then what was your point?

ETA: In the second half of this video, put the point of a pencil at the intersection of the north east corner of WTC 7 where it intersects the white building in front of it. Note that the corner and thus the building is falling straight down during the free fall accaleration part of the collapse.
http://www.youtube.com/watch?v=OmL9F-TSIes

ETA: Correction - the north west corner is falling to the north for about the first 12 feet.
Using the cursor instead of a pencil you can detect a very slight movement to the north at the east end. This indicates that the supporting structure on the north side was removed a fraction of a second before the south side.

 

[Christopher7]

The cannonball example takes the "free fall" issue into a two dimensional single system scenario. If you cannot understand 2D single system there is little hope of understanding 3D and (at least) dual systems which is the minimum level of complexity needed to comprehend WTC7 collapse.

I stand corrected. The '"only force" refers to vertical, not horizontal.

Chris, I apologize for saying that you do not know what you are talking about in this instance - but not where you compare a stick to structural steel.

As I noted in my last post, the argument is moot because WTC 7 was not falling to the side during the period of free fall acceleration.

ETC: See ETA above.

 

[chrismohr]

I stand corrected. The '"only force" refers to vertical, not horizontal.

Chris, I apologize for saying that you do not know what you are talking about in this instance - but not where you compare a stick to structural steel.

As I noted in my last post, the argument is moot because WTC 7 was not falling to the side during the period of free fall acceleration.

Apology accepted.
The stick analogy has one point only: to show how a column of steel can bend just a tiny bit at first, then, when it buckles, it loses almost all strength. There's a sudden reduction of strength. If that analogy rings false (and maybe it does), it was just a tool to explain how a column can start out just bending slowly and then suddenly lose almost all resistance. Frankly, I understand the differences between wood and steel columns better than I understand what BasqueArch is talking about, who says the principle is actually the same.
I was right about the cannonball analogy, but as for your question about what I meant by Building 7's lean in Tri's pictures, I won't engage with you further until you agree to stop calling me unqualified and ignorant. Your call mate.

 

[Christopher7]

Apology accepted.
The stick analogy has one point only: to show how a column of steel can bend just a tiny bit at first, then, when it buckles, it loses almost all strength. There's a sudden reduction of strength. If that analogy rings false (and maybe it does), it was just a tool to explain how a column can start out just bending slowly and then suddenly lose almost all resistance.

Incorrect on a couple counts. A stick [or 2x4] breaks loosing all its strength suddenly. As a carpenter I have experience with this. On the other hand, a steel H beam [a more accurate term than I beam] does not break or loose almost all its strength suddenly like a piece of wood and the comparison does show a lack of understanding of the physical properties of both.

Furthermore, when there are many H beam columns connected with moment frames, there is always significant resistance as can be seen in the NIST collapse simulation I posted. The columns are bending in a random manner during the period of free fall acceleration confirming that the NIST model is NOT falling at free fall acceleration.

I was right about the cannonball analogy, but as for your question about what I meant by Building 7's lean in Tri's pictures, I won't engage with you further until you agree to stop calling me unqualified and ignorant. Your call mate.

We are all "ignorant" to one degree or another. Ignorant just means not knowing and none of us knows everything. I do contend that you are unqualified to speculate on the mechanics of the collapse because of your stick comparison and other statements you have made that I will discuss later but I have other work to do right now.

 

[GlennB]

Incorrect on a couple counts. A stick [or 2x4] breaks loosing all its strength suddenly. As a carpenter I have experience with this. On the other hand, a steel H beam [a more accurate term than I beam] does not break or loose almost all its strength suddenly like a piece of wood and the comparison does show a lack of understanding of the physical properties of both.

Except where the column is made up of multiple sub-columns welded and/or bolted together. Then the joint breaks and the stick analogy is accurate. It bends then it breaks.

This is precisely what was witnessed on 9/11 for all 3 buildings.

For WTC7 all that is required is for a ~100' section to first flex (Stage 1 in the NIST graph) then break, allowing 100' of unresisted fall (Stage 2).

One fatal flaw in your theory, Chris, is that you cannot explain Stage 1.

 

[ozeco41]

I stand corrected. The '"only force" refers to vertical, not horizontal....

Noted -- Thanks.

NOW

Both Chris's

The wooden stick is IMNSHO a poor example and probably more so when used in a presentation for lay audiences. Why? Because it is readily misunderstood whether through innocence or deliberate misinterpretation.

It is true as several astute members have stated that the initial failure point for a timber column is the identical Euler Buckling which steel columns undergo. That failure occurs long before the point of snapping. It is the failure point where the column cannot sustain designed loads - actually a bit beyond that point but let me not digress into factors of safety. It is the point that engineers call failure - long before the average layperson would call "failed".

The final point of breaking which the lay audience sees as failure with a wooden stick is very different to what happens with a steel column. The steel column does not snap in the catastrophic separation of splinters that the wooden stick undergoes. Sure an assembly of columns bolted or welded may fail at the bolt or weld joints in a manner roughly similar to the snapping of a wooden stick.

But, in hindsight ChrisM, you could possible have chosen a better example. And C7 is partially correct - whether the point is of any significance structurally is another matter.

However remember that the only reason we are discussing this is because a truther operating in nit-pick mode has identified the issue.

There is no way that any presentation can be made immune to the sort of determined nit-picking that truthers routinely engage in. And no matter how many nits you find and remove the determined truther will find or invent more. So trying to eliminate the opportunities is a forlorn hope.

Why don't you ChrisM wait and see if any honest lay person comments on the issue. After all the target audience is lay persons, preferably honest ones. Including any remaining truthers out there who are amenable to reasoned explanation and do not have minds like concrete -- all mixed up and set rigid.

 

[fourtoe]

That's correct. The area of the kink started down a split second before the rest of the north face and therefore was falling ever so slightly faster. This is done in controlled demolition to get a building to fall inward from the two ends. It didn't work perfectly but it did prevent serious damage to the Post Office.

You said this awhile back before the epic definition of free fall discussion started and it went pretty much unchallenged.

So I'm not sure if this has been discussed already, but is there a reason why the CD of WTC7 was set up in such a way to not significantly damage the Post Office and why weren't the other surrounding structures considered as well?

Also I think some of you guys are being a little too mean to tmd for his question he asked, it seemed pretty genuine, IMO. I know in other threads he has said some ridiculous things and stuff but that question he asked seemed sincere this time around.

To us unworthy shills and trolls, this thread seems pretty daunting so be ready for our asking questions that might seem like no-brainers to everyone else.
Here's an example of what I mean: Chandler claims that as the WTC7 collapses no internal forces are acting upon the structure or can't effect the structure? As someone who got a C- in calculus based physics back in 2008 (so long ago), that seems like a bizarre claim to make. Did I just interpret that claim incorrectly? I first saw this claim mentioned in this post by C7.

 

[ozeco41]

I spotted the alleged claim by Chandler and commented (very) briefly in this post: http://www.internationalskeptics.com/forums/showthread.php?postid=8101975#post8101975

I followed up with a comprehensive explanation in this post: http://www.internationalskeptics.com/forums/showthread.php?postid=8103018#post8103018

In which post I made this comment: "If Chandler did make that statement he is wrong. Obviously wrong and at an elementary level of physics."

No-one has responded to my comment including C7 for whose benefit I posted it.

 

[grandmastershek]

Except where the column is made up of multiple sub-columns welded and/or bolted together. Then the joint breaks and the stick analogy is accurate. It bends then it breaks.

This is precisely what was witnessed on 9/11 for all 3 buildings.

For WTC7 all that is required is for a ~100' section to first flex (Stage 1 in the NIST graph) then break, allowing 100' of unresisted fall (Stage 2).

One fatal flaw in your theory, Chris, is that you cannot explain Stage 1.

They can explain very little, thats why they focus on the minutae that fits their pet theories. If they addressed all the facts it becomes blatantly apparent how farcical the whole proposition of CD is; eg C7 is now talking about how the kink actually supports CD as the kink apparently was to prevent hitting the post office, because as we all know the damage factor was an obvious concern. But since the kink contradicts the "evenly/symmetrically collapsed" nonsense he must incorporate it someway to rationalize the delusion.

 

[ozeco41]

They can explain very little, thats why they focus on the minutae that fits their pet theories. If they addressed all the facts it becomes blatantly apparent how farcical the whole proposition of CD is; eg C7 is now talking about how the kink actually supports CD as the kink apparently was to prevent hitting the post office, because as we all know the damage factor was an obvious concern. But since the kink contradicts the "evenly/symmetrically collapsed" nonsense he must incorporate it someway to rationalize the delusion.

If you look at that famous video showing the East Penthouse sinking into the rest etc

It is obvious that support has gone from under the Penthouse. Since the façade is not initially moving it means that the internals have collapsed but not yet the façade. And the column right under the E Penthouse is Col 79.

Explaining the details from there is icing on the cake. (Frosting???)

Since there was no CD why do we need more info?

 

[sheeplesnshills]

Sheeples, cannonballs don't go into orbit unless there is no atmosphere and they get shot out at 17,000 mph or so. But to compensate for earth's curvature, let's posit that for 20 miles the land starting at the base of the cliff curves upward with the same curvature that the Earth curves down. THEN the frigging cannonballs hit ground at the same time, yes?

Yes. (probably.....)

One possibility for a point on an object appearing to reach or even exceed 1g acceleration in that if the object is rotating around a near horizontal axis. The object overall is accelerating at less than one G but since the point at the top is rotating it appears to be moving faster and thus accelerating faster than G. Similarly a point at the bottom would appear to be accelerating slower. As WTC fell it leaned towards the south ie the wall was rotating around an axis. Any point at the top of that wall would appear to be falling faster than the wall as a whole is and thus would appear to be accelerating at a higher rate than the wall as a whole was.

 

[000063]

Possibly? Aparently you don't know the difference between the physical qualities of steel and wood either.

A pencil is different from a stick, but I can still snap both in similar fashion.

His insistence that the entire upper portion was not falling at free fall acceleration is another example.

The north face descended at gravitational acceleration for about 100 feet.

The entire building above the buckled-column* region then moved downward in a single unit, as observed

The north face is part of the entire upper portion.

Therefore, the entire upper portion moved downward in a single unit at free fall acceleration.

To assert otherwise is saying that 2 + 2 is not equal to 4.

* Incorrect assumption. Buckling steel columns provide resistance and free fall acceleration means no resistance.

Textbook division fallacy.

[qimg]http://img402.imageshack.us/img402/7267/nistwtc7modelvideo14s16.jpg[/qimg]

These frames from the NIST computer simulation show that the columns are buckling and therefore providing resistance during the period of free fall acceleration. Please note that they are NOT breaking like sticks.

So you're making a point about the external structure of the building using a simulation showing the internal structure?

And one showing significant portions of the upper structure had already collapsed? That is, the bits under the E. Penthouse?

Let me guess, you're going to try and say that most of the upper portion fell at free fall, despite just claiming that the entire thing did. Then I or someone else will point out that you were saying because the north face was moving at FFS, the entire upper portion was, yet you would now be claiming that most of the upper portion fell at FFS without admitting that you were wrong. And then you just keep digging or ignore such posts.

You're not saying 2+2=4, you're saying 2=4.

 

[Sabretooth]

Incorrect on a couple counts. A stick [or 2x4] breaks loosing all its strength suddenly. As a carpenter I have experience with this. On the other hand, a steel H beam [a more accurate term than I beam] does not break or loose almost all its strength suddenly like a piece of wood and the comparison does show a lack of understanding of the physical properties of both.

Regardless. The fact remains that even H/I beams have a limit to their integrity. Heat from fire removed ~50% of the strength. If you put enough weight on anything, it will suffer full critical failure without noticeable resistance.

Much like standing on an empty soda can. You could feasibly place a 200 lb weight on a soda can and it would support that weight. However, any minute failure would crush said can within a blink of an eye...and at "freefall"...as the can would have zero integrity.

(Before you accuse me of comparing steel beams to a soda can, that's not what I said. I'm only offering a simple analogy to show that items that have structural integrity will have zero resistance once that integrity has been breached.)

IIRC, WTC7 only showed a brief period of freefall. Which is not to be unexpected when you have critical buckling failure of an already weakened support structure. I don't understand how this is lost on you.

 

[000063]

Regardless. The fact remains that even H/I beams have a limit to their integrity. Heat from fire removed ~50% of the strength. If you put enough weight on anything, it will suffer full critical failure without noticeable resistance.

Much like standing on an empty soda can. You could feasibly place a 200 lb weight on a soda can and it would support that weight. However, any minute failure would crush said can within a blink of an eye...and at "freefall"...as the can would have zero integrity.

(Before you accuse me of comparing steel beams to a soda can, that's not what I said. I'm only offering a simple analogy to show that items that have structural integrity will have zero resistance once that integrity has been breached.)

IIRC, WTC7 only showed a brief period of freefall. Which is not to be unexpected when you have critical buckling failure of an already weakened support structure. I don't understand how this is lost on you.

I actually used to do the soda can thing. Hurt myself when I used a short pencil to poke in the side, and the subject's foot came down on my finger.

I'm not sure it is lost. He just keeps dismissing the analogy because a steel beam is not identical to a stick, while ignoring that it doesn't have to be identical for a comparison to be valid. I can compare an apple to a fire truck in that they are both red, but that doesn't mean they're identical.

 

[chrismohr]

Chris,

Not too bad. You got 2/4.

We'll give C7 a chance to try his hand, if he wants, and tomorrow I'll post the "whys".


Tom

PS. Nope, not a teacher. I'm a working mechanical engineer (bioengineering). But I have taught engineering dynamics for freshmen/sophmore college engineering students. That was a lot of fun.

And I've helped raise a passel of kids thru their "science fair" days.

PPS. You guessed right on the bullet spinning. For aerodynamic stabilization. Same as with a football. No spin, you can't throw it far or accurate. It'll start to tumble.

"Rifling" is helical grooves in the barrel that dig into the sides of the soft, lead bullet, that cause the bullet to spin. Makes it much, much, much more stable in flight (like a gyroscope or a frisbee) & therefore much more accurate.

A spinning bullet (whether shot or dropped) will maintain it's original orientation. A non-spinning one will orient itself (weather-cock) to the apparent wind to minimize drag forces.

Care to adjust any of your answers?

;-)

Hi TFK,

If I make any changes on your little quiz, it would be to say that every pair of objects (arrows, bullets, cannonballs) falls to the ground at the same rate. I know that if you dropped a piloted glider plane off a cliff and also towed another piloted glider plane up to 70 mph with an airplane out over the cliff and released it at the same altitude as cliff's edge, the pilot of the plane-towed glider could convert some of the horizontal momentum into lift, which would give that pilot an advantage over the guy who just went over the cliff in HIS glider.

But with a bullet, or an arrow, I'm thinking maybe there is some lift that comes from the feather or the spinning bullet, but I can't see it in any obvious way. That's why I might just consider defaulting back to every pair of objects falling at an identical rate to each other.

And this is why I'm an empiricist... these thought experiments are good learning tools, and they generate interesting hypotheses, but really now, until you shoot/drop two ARROWS etc. you can't really know, can you? Logic and thought can be better used to interpret and analyze data from actual experiments. Make your conclusion first and then try to fit the facts, and you get reverse scientific method. That's why Aristotle said a spider has six legs, and why... oh, never mind.

 

[tfk]

I stand corrected. The '"only force" refers to vertical, not horizontal.

Chris, I apologize for saying that you do not know what you are talking about in this instance - but not where you compare a stick to structural steel.

As I noted in my last post, the argument is moot because WTC 7 was not falling to the side during the period of free fall acceleration.

ETC: See ETA above.

And yet i vividly remember a video of a structural engineer at MIT (Tom Eager, IIRC) demonstrating exactly what you are talking about (buckling columns) using weights for floors and wooden dowels for steel columns.

Is that MIT structural engineering professor also not as astute as you are, Chris7, when it comes to producing structural analogies?

tk

 

[sheeplesnshills]

Incorrect on a couple counts. A stick [or 2x4] breaks loosing all its strength suddenly. As a carpenter I have experience with this. On the other hand, a steel H beam [a more accurate term than I beam] does not break or loose almost all its strength suddenly like a piece of wood and the comparison does show a lack of understanding of the physical properties of both.

This would be news to Euler, Runge, Kutta and others.......

http://en.wikipedia.org/wiki/Buckling


And I've heard that Miners prefer Wood pit props because they give more warning before failing.

 

[DGM]

Hi TFK,

If I make any changes on your little quiz, it would be to say that every pair of objects (arrows, bullets, cannonballs) falls to the ground at the same rate. I know that if you dropped a piloted glider plane off a cliff and also towed another piloted glider plane up to 70 mph with an airplane out over the cliff and released it at the same altitude as cliff's edge, the pilot of the plane-towed glider could convert some of the horizontal momentum into lift, which would give that pilot an advantage over the guy who just went over the cliff in HIS glider.

I believe the correct answer is all will fall at the same rate except for the dropped arrow (the entire arrow that is).

The dropped arrow would rotate (due to the drag of the flights) causing the tip of the arrow to exceed the acceleration of G (while the center of mass will not). This will give the arrow (tip) a slight advantage. (it's why a dropped arrow will stick in the ground if given enough distance).

 

[Clayton Moore]

The WTC7 free fall means a large portion of the building immediately beneath the falling portion had been eliminated.