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it does not have too... getting and reporting bad info is all a part of the news game, the point is not whether the BBC reported that it had fallen.dear sister jones 2.25 secs of free fall is meaningless..
Questions and Answers about the NIST WTC 7 Investigation (09/17/2010, ARCHIVE, incorporated into 9/19/2011 update)
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In a video, it appears that WTC 7 is descending in free fall, something that would not occur in the structural collapse that you describe. How can you ignore basic laws of physics?
In the draft WTC 7 report (released Aug. 21, 2008; available at WTC Disaster Study), NIST stated that the north face of the building descended 18 stories (the portion of the collapse visible in the video) in 5.4 seconds, based on video analysis of the building collapse. This time period is 40 percent longer than the 3.9 seconds this process would have taken if the north face of the building had descended solely under free fall conditions. During the public comment period on the draft report, NIST was asked to confirm this time difference and define the reasons for it in greater detail.
To further clarify the descent of the north face, NIST recorded the downward displacement of a point near the center of the roofline from first movement until the north face was no longer visible in the video. Numerical analyses were conducted to calculate the velocity and acceleration of the roofline point from the time-dependent displacement data. The instant at which vertical motion of the roofline first occurred was determined by tracking the numerical value of the brightness of a pixel (a single element in the video image) at the roofline. This pixel became brighter as the roofline began to descend because the color of the pixel started to change from that of the building façade to the lighter color of the sky.
The approach taken by NIST is summarized in Section 3.6 of the final summary report, NCSTAR 1A (released Nov. 20, 2008; available at WTC Disaster Study) and detailed in Section 12.5.3 of NIST NCSTAR 1-9 (available at WTC Disaster Study).
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 timecompared to the 3.9 second free fall timewas 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.Questions and Answers about the NIST WTC 7 Investigation
Still doesn't explain why the BBC reported that building 7 fell before it actually fell.
A mistake would be to report the incorrect building had fallen, not report that the building had fallen before it fell.
the point is it was standing long after they reported it fallen.
that alone would for any one with correctly functioning set of eyes and brain know that the report was wrong.
the BBC did retract the story and apologized.
besides twoofers never let little things like facts get in the way.
the BBC did retract the story and apologized.
Retract what that they were told to report that building 7 fell?
No a mistake is reporting that obama is dead that's a mistake the people who told the reporter to say building 7 fell made the mistake a little early.it does not have too... getting and reporting bad info is all a part of the news game, the point is not whether the BBC reported that it had fallen.
the point is it was standing long after they reported it fallen.