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gyroscope

(1,443 posts)
Tue Nov 11, 2014, 06:06 PM Nov 2014

Offical explanation for twin tower collapses can be disproven in one word

Acceleration.

Simple physics: When one object (lets call it A) is dropped onto another similar, stationary object (B) the impact will cause A to slow down greatly. When a cue ball strikes a billiard bill, the cue ball is slowed drastically, and very noticeably, by the impact and quickly comes to a stop. I think we can all agree with this. No one in their right mind could disagree with this basic principle.

But the upper block (above the airplane impact zone) of the respective north and south towers is NOT decelerating as it falls and 'crushes down' the (much larger) lower block as we would expect. The upper block is actually speeding up, not slowing down at all as it falls toward the ground. Hence the official 'pile driver' explanation to explain the collapse of the twin towers is pure BS, because it violates every physical law known to man.

Unless the lower section of the towers were made of jello or toothpicks, the upper part should have slowed drastically as it impacted the lower part. But as plainly seen in the collapse videos, it is actually speeding up as it races toward the ground; moving through the more massive lower section as if it weren't even there.


Official FAQs, explaining the government's 'pile driver' theory for the collapse of the twin towers
(good for a laugh or two)

http://www.nist.gov/el/disasterstudies/wtc/faqs_wtctowers.cfm

6 replies = new reply since forum marked as read
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Offical explanation for twin tower collapses can be disproven in one word (Original Post) gyroscope Nov 2014 OP
How does it violate the speed of light? GeorgeGist Nov 2014 #1
Post removed Post removed Nov 2014 #2
+1 n/t zappaman Nov 2014 #4
The towers fell at the speed of unsound Blue Owl Nov 2014 #3
Your conclusion can be invalidated with one graph William Seger Nov 2014 #5
Deceleration isn't even required. AZCat Nov 2014 #6

Response to GeorgeGist (Reply #1)

William Seger

(10,778 posts)
5. Your conclusion can be invalidated with one graph
Wed Nov 12, 2014, 12:54 AM
Nov 2014

There was deceleration, as shown by measurements and analysis by femr2 (who happens to be a "truther&quot . The bottom line is the measured velocity of the NW roof corner:



So Tony Szamboti's claim that there was no "jolt" is false, and his later claim that it should have been larger is based on faulty logic. Specifically, Tony claims that if the scenario used in Bazant's analysis is an accurate description of what happened, then there should have been a large deceleration caused by the "force amplification" necessary to buckle the columns. No jolt of the "expected" magnitude was observed, says Tony, so that scenario must not be an accurate description of what happened. Well, duh, anyone who actually understood Bazant's analysis already knew that, because that was never the intent. The analysis was based on a one-dimensional model in which the upper block had gravitational potential energy by simply being 13 feet higher than the floors below, which was converted to kinetic energy by falling that distance. Bazant analyzed whether or not the columns below could have absorbed that energy without buckling. The analysis demonstrates that the energy was far more than the columns could have absorbed as strain energy. The conclusion is that even if all the columns had acted in unison to absorb maximum energy by compressing, they would have buckled and the collapse was bound to proceed. But we already know that the top block did not drop cleanly and impact column-on-column to allow that maximal energy absorption to happen. Bazant explicitly denied that that was a "realistic" scenario and mentioned other failure modes that certainly happened -- e.g. ripping floors away from columns -- but notes that those failure modes would have absorbed even less energy than column buckling, so total collapse was simply unavoidable.

Furthermore, even for columns that did buckle, the tilt of the top block meant that they didn't all buckle at the same time, so there's no reason to expect to see a single massive jolt of the top block: the "jolt" they collectively produced was spread out over time. But Tony simply ignored all the many reasons why the roof should not be expected to show the jolt he claimed, and instead continues to insist that magical silent explosives are the only possible explanation. If you're waiting for his arguments to be taken seriously in the engineering community, I predict you'll be waiting a long, long time.

The real significance of Bazant's analysis is that if anyone who wants to claim that the structure should have been able to halt the collapse, then they need to explain how all that energy would have been absorbed. If you don't understand why that's so, then you are in no position to be making claims about the physics of the situation. And if you don't have a valid explanation, then you don't have a case. And that's exactly where the "truth movement" is, despite many years of hand-waving claims based on imaginary physics by Richard Gage's "experts."

AZCat

(8,339 posts)
6. Deceleration isn't even required.
Fri Nov 14, 2014, 07:39 AM
Nov 2014

A decrease in acceleration is also an indication of a transfer of energy from the upper block to the rest of the building. Tony butchered this for years, until he decided to unilaterally redefine common physics terms so he wouldn't look quite so foolish.

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