Quote:
Originally Posted by MediaGuy
You might have read one of the NIST reports, whose version of events changed a few times btw - but apparently you didn't read the final report - which was prompted by NIST frontman Shyan Sunder being publically confronted by a high school physics teacher on the matter.
Final Report:
http://www.nist.gov/customcf/get_pdf.cfm?pub_id=861610
Goto page 45
NIST announces stage 2 as gravitational acceleration. It's couched in all this sciencespeak so they don't have to make any conclusions from the fact, but there it is.
On http://www.nist.gov/public_affairs/f..._qa_082108.cfm NIST defines or "simplifies" gravitional acceleration as "free fall".
Problem is that the majority of these people have simply not looked at the evidence, from not believing the possibility.
Most of those who are vocal in demanding at least an investigation (which was never actually conductied) were once in denial until they were presented with the facts.
You can't really believe it makes no difference whether the building/s was/were destroyed "naturally" or if they were demolished...
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It's right there on the page you quoted. You can't just take one stage of the building falling and ignore the remaining two.
Quote:
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
This analysis showed that the 40 percent longer descent time?compared to the 3.9 second free fall time?was due primarily to Stage 1, which corresponded to the buckling of the exterior columns in the lower stories of the north face. During Stage 2, the north face descended essentially in free fall, indicating negligible support from the structure below. This is consistent with the structural analysis model which showed the exterior columns buckling and losing their capacity to support the loads from the structure above. In Stage 3, the acceleration decreased as the upper portion of the north face encountered increased resistance from the collapsed structure and the debris pile below.
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The building did not fall at free fall speeds. It fell 40% slower.