The explanation I’ve heard is that once few of the top floors fall on one of the floors below them, the effect is sort of like it was being hit with a hammer, all the supporting columns of each floor below snap instantly as they are hit, so it’s almost free fall from then on.
Be careful not to explain data that turn out to be false. IIRC (someone else could look it up if they were really interested) the “free-fall” part is bogus, the free-fall time was 9 seconds and the actual time was 15 seconds or something like that.
The explanation I’ve heard is that once few of the top floors fall on one of the floors below them, the effect is sort of like it was being hit with a hammer, all the supporting columns of each floor below snap instantly as they are hit, so it’s almost free fall from then on.
Be careful not to explain data that turn out to be false. IIRC (someone else could look it up if they were really interested) the “free-fall” part is bogus, the free-fall time was 9 seconds and the actual time was 15 seconds or something like that.