Basic Newtonian Mechanics question

[yodermon]

Consider these pictures:




At what point in time did these "compression ejections" or "squibs" occur, compared to an object in free-fall released at from the floor at the start of the collapse?

Thanks.

[philb]

1. There were lots of reports of upper level explosions and squibs by Firefig

the NY Firefighters and Policemen.
See the Firefighter statement thread.

this seems the report of the squib explosions that toppled the top of WTC2 and was the start of the "collapse"

( (pa-police-reports04.pdf page 6) Det. Thomas M. Inman
Memorandum Page 1
“As a roll call was being taken of the responding Detectives, Tower #2 began to collapse. This occurred after a secondary explosion on the west side of the tower that appeared to take place in the high 60’s. The area above the secondary explosion actually leaned to the west and then the collapse took place.”

pa-police-reports04.pdf pages 4&5) P.O. Middleton #1207 Memorandum Page 1
“I was approximately one block away from Tower One when Tower Two appeared to explode at the roof top and several floors below. Then fire balls and debris shot out of the windows and rocketed into the skies and fall below.”

and WTC1
(pa-police-reports04.pdf pages 4&5) P.O. Middleton # 1207 Memorandum Page 2
“As I continued to wave them back periodically you would hear a loud boom go off at the top of tower one. As the building continued to burn and emergency equipment kept on responding stirring up the dust and debris in the streets. After approximately 15 minutes suddenly there was another loud boom at the upper floors, then there was a series of smaller explosions which appeared to go completely around the building at the upper floors. And another loud earth- shattering blast with a large fire ball which blew out more debris and at that point everyone began to run north on West Broad Street.”
(pa-police-reports04.pdf page 88) Detective Salvatore Piro
Port Authority of NY & NJ Memorandum Page 1
“At that point, I heard a low sounding boom and the smoke intensified. There was more debris falling and as I heard a big roar, I saw Tower One coming down.”
(pa-transcript044.pdf page 18) WTC Ch 22 – SHO PD DESK – 2131 Page 18
MALE A: There’s been … been numerous explosions on the … like 89th, 92nd floor."