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Re: energy and mass

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Am Freitag000027, 27.03.2026 um 17:17 schrieb Bill Sloman:
> On 27/03/2026 7:13 pm, Thomas Heger wrote:
>> Am Donnerstag000026, 26.03.2026 um 15:00 schrieb Thomas Heger:
>> ...
>>>>> So, material objects with a mass larger than 20 to of steel and 
>>>>> concrete 'dustified' in mid air and were blown away.
>>>>
>>>> They got broken up in a series of smaller collisions, as each floor 
>>>> fell onto the floor below it, and got further broken up by each 
>>>> impact in succession.
>>>
>>> That's not how things fall, if they hit something hard below.
>>>
>>> If you would drop something breakable from some height upon something 
>>> breakable, but with high resistance against breaks, you would expect 
>>> a different pattern:
>>>
>>> the upper part of a collision would cause breaks in the parts below, 
>>> but also breaks of the same kind in itself, because the both parts 
>>> were assumed to have the same strength.
> 
> What happened to the Twin Towers was that the towers caught on fire and 
> got hot, weakening both the steel frame and the concrete.
> 
> When they got weak enough the Towers collapsed, floor by floor. About 
> the only stuff that fell a long way were the supporting columns, which 
> leaned way from the building and eventually fell outwards, hitting 
> adjacent building. Each floor collapsed inwards, stopping at the next 
> floor (but not for long) before the next floor failed
> 
>>> If we concentrate on the upper part only (for a moment), we would 
>>> expect parts of the falling piece to splinter off and fall partly 
>>> outside of the former building shape, hence would fall in free fall 
>>> outside down to the ground.
> 
> Why? It's all tied together by a steel frame, which may be failing,
> But stuff isn't going to "splinter off". There don't seem to be any 
> reports of that.

The entire neighborhood of the twin-towers got struck by large sections 
of the perimeterwalls.

Some of these sections were HUGE and hit neighboring buildings up to 
several hundred meters away (like e.g. bulting WTC 7).

That's why the assumption of simple free fall drop wasn't unlikely at all.
> 
>>> Doesn't matter that much, what percentage would break of the upper 
>>> part, because at least some parts would do that.
> 
> An unsupported assumption.

WHAT???

If a building collapses under the own gravity, it is actually VERY 
likely, that the pieces fall down to the ground in one way or the other.
> 
>>> But even at the height of the actual impact zones, sections of the 
>>> perimeter wall of the twin towers would fall down with enormous mass 
>>> and velocity.
> 
> I saw it happen on TV. They didn't.

No, they didn't.

But isn't that astonishing??

I mean: you drop a piece of the enromous buildings composed from steel 
and concrete and a weight of a locomotive from a skyscraper.

And it didn't hit the ground!

Instead it turned to dust in mid-air and gets blown away.

If you would think, that such a behavior is 'natural', you were a 
hopeless case.


>>> IoW: possibly you were right and not that many 'cannon balls' or 
>>> 'fright trains' would have hit the ground, but certainly some.
> 
> Why "certainly"?

Well, in 'collapse under the own weight' I would see an influence of 
Earth' gravity.

What gravity 'really' is, that is not perfectly understood. But at least 
we know, that gravity makes unsupported things drop down.

As we have some confidence in gravity, we could assume with certainty, 
that heavy objects do not float in the air.

>>> But apparently this didn't happen, because every single of those 
>>> sections of the perimeter walls would have pierced through the street 
>>> level like a hot knife though butter.
> 
> Really?

The kinetic energy and the momentum of falling debris would have been 
enormous.

E.g. a piece of 'moderate' mass (by WTC standards) would have, say, 20 to.

If dropped from a hight of 400 m it would have a kinetic energie at 
ground level of about 78.000.000 Joules.

That is just enormous and about five times the kinetic energy of an 
artillery shell.

> 
>>> In this didn't happen, because the street level was mainly intact.
>>>
>>> You could easily see that, if you look at any pictures of the 
>>> aftermath of 9/11, which show the remains of the twin-towers.
>>>
>>> E.g. you can see, if you look carefully, remains of fire-trucks and 
>>> other cars in the rubble, which remained astonishingly undamaged. For 
>>> instance some had still unbroken windows.
>>>
>>> This wouldn't be possible, if a just screw-driver would fall from 
>>> that height, let alone sections of the perimeter wall, weighing more 
>>> then 20 tons.
> 
> A screw driver has a rather low terminal velocity. A human falling from 
> any height can't reach a terminal velocity above about 190km/hour.
> 
> It the perimeter wall broken up into less massive pieces - only 10 or 
> 20kgm - they'd have a lower terminal velocity.

Sure, but the pieces hadn't.

The twintowers were build from-steel beams with insane masses,

These steel-beams had thick wall and large dimensions.

There ware also used in groups of beams in the perimeterwalls and were 
welded together.

A few kg are just not the rigth dimensions for the sections of the walls.

These sections had masses well over twenty to.


> <snipped calculations about imagined fragments>
> 
>> But each tower consisted of more than half a million tons, hence not 
>> only one piece would fall down, but more than 25.000 pieces.
> 
> You'd like each piece to have weighed about 20 tons, but you haven't 
> explained why it should have.


Well, we usually have smaller pieces and larger pieces and some sort of 
mean 'piece-size'.

20 to was just a guess. But you could chose other sizes, if you like.

How about 10 to?

TH

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Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-03-18 09:11 +0100
  Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-18 21:28 +1100
    Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-03-19 12:10 +0100
      Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-20 01:35 +1100
        Re: energy and mass Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-19 07:44 -0700
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              Re: energy and mass Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-20 09:58 -0700
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        Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-03-20 11:00 +0100
          Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-21 02:54 +1100
            Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-03-22 10:31 +0100
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                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-23 22:31 +1100
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                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-03-29 09:56 +0200
                Re: energy and mass Daren Remond <ndno@dmrndd.us> - 2026-03-29 13:04 +0000
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                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-30 10:17 +0200
                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-03-31 09:13 +0200
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                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-03-27 09:13 +0100
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-28 03:17 +1100
                Re: energy and mass Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-27 10:39 -0700
                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-03-29 10:19 +0200
                Re: energy and mass Cloro Sandiford <iofnd@dosc.us> - 2026-03-29 13:01 +0000
                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-03-30 08:31 +0200
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-31 02:45 +1100
                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-03-31 09:39 +0200
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-31 23:10 +1100
                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-04-01 09:47 +0200
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-04-02 02:34 +1100
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-04-01 18:23 +0200
                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-04-03 10:12 +0200
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                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-04-05 09:57 +0200
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-04-06 02:53 +1000
                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-04-06 13:09 +0200
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-04-07 04:11 +1000
                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-04-08 09:13 +0200
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-04-08 22:56 +1000
                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-04-03 10:31 +0200
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-04-04 03:16 +1100
                Re: energy and mass The Starmaker <starmaker@ix.netcom.com> - 2026-04-03 09:38 -0700
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-04-04 04:15 +1100
                Re: energy and mass The Starmaker <starmaker@ix.netcom.com> - 2026-04-03 23:18 -0700
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-04-04 21:37 +1100
                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-04-05 10:14 +0200
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-04-05 20:58 +1000
                Re: energy and mass Thomas Heger <ttt_heg@web.de> - 2026-04-06 12:51 +0200
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-04-07 04:27 +1000
      Re: energy and mass The Starmaker <starmaker@ix.netcom.com> - 2026-03-19 11:17 -0700

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