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Re: Why the 3rd skyscraper came freefalling down on 9/11

Subject: Re: Why the 3rd skyscraper came freefalling down on 9/11
From: "Antony Clements" <antony.clements@xxxxxxxxxxxxxxx>
Date: Sun, 31 Dec 2006 16:09:27 +1100
Newsgroups: sci.physics, soc.culture.usa, sci.crypt, sci.lang
> So you have worked out that the proposition you put forth earlier is crap 
> (and not a lazy typo like your latest posts are trying to claim - hint 
> when you screw up admit it).
>
> I'm hopeful the penny has dropped.

i'm going to copy and paste Mr Taylor's last reply

>> Any object, with any weight, will fall with a CONSTANT ACCELERATION of
>> 9.8m/s/s.  UNLESS you include air resistance, where the force from
>> gravity (dependant on the mass of the object) will eventually be
>> cancelled out by the force from the air resistance (dependant on the
>> shape and speed of the object).  At that point it will have
>> a constant velocity which depends on the mass and shape of the object.
>>
>> I did once say you were including air resistance, but I was most
>> certainly not supporting that claim.
>
> which is essentially what i have said. objects only fall at 9.8m/s (yes i 
> know it is per second squared but i really couldn't be bothere fishing 
> through the character map to find the little 2 or trying to remember it's 
> ascii code)

>So write m/s/s, or at least call it an acceleration.  m/s _is_ a velocity
>(as you said).  9.8m/s is nothing special as far as gravity is concerned.
>9.8m/s/s is a special acceleration.

> in a vacuum, which in reality, only exists in space (for the most part but 
> not entirely a vacuum but the closest one can get in nature) or in a 
> vacuum tube irrespective of size or shape (i said that in one of my posts 
> to Bryan).

>OK.

>This I can accept as a rather vague, but quite correct, explaination:

> the gravity of earth is a constant (unless for some reason the magma 
> ceases to be magma and becomes part of the core), the effect of gravity on 
> a mass WHEN COUPLED WITH RESISTANCE (i say resistance because i am 
> referring to any gaseus substance of equal density and viscousity to our 
> nitrogen/oxygen atmosphere) is not.

> is that a better statement Mr Taylor?

>Yes.

> you also just echoed another statement i made to Bryan that the EFFECT of 
> gravity is in part dependant on the mass of the object "where the force 
> from gravity (dependant on the mass of the object)" and that the effect of 
> resistance is dependant on the area of the object exposed to that 
> resistance "will eventually be cancelled out by the force from the air 
> resistance (dependant on the shape and speed of the object)." NOW you can 
> accuse me of qouting you for support. but to everyone, i say whatever.

>Yes, that is right.  What is not right is describing a force as
>.an acceleration, an acceleration as a velocity, or m/s/s as m/s.
>Or claiming that all objects fall at a constant velocity.
>All of which you did, possibly by mistake.

so no it wasn't crap, just very much simplified bordering on crap.



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