From: Lee Corbin (lcorbin@tsoft.com)
Date: Sun Oct 13 2002 - 10:39:03 MDT
Mike Lorry (not Robert Bradbury) originally wrote
http://www.extropy.org/exi-lists/extropians/2111.html
which contains the passage
> Each collapse triggered a 2.7 richter earthquake. Each tower
> was about 40,000 tons of material (not pounds). That's 80
> million pounds of material, striking the earth at 250 mph (367
> fps). Kinetic energy equals mass times velocity squared, or
> 10,775,120,000,000 ft-lbs/sec for each tower collapse. How
> many tons of TNT is that equal to?
Alfio writes today
> On Sat, 12 Oct 2002, Lee Corbin wrote:
>
> >Anyway, your 1.07 x 10^13 joules works out to about .0027
> >megaton, or 2.7 thousand tons of TNT. The little Hiroshima
> >bomb was 5,000 kilo-tons, I believe.
>
> That would be 5 megatons, which is way too much, I believe.
> At this address
You're right about Hiroshima; my figure above is way wrong.
> http://www.chandrella.org/documents/nuclear/Hiroshima_and_Nagasaki.shtml
>
> I find a suprisingly low quote of 15 kilotons. The Nagasaki bomb was a bit
> bigger, 21 kilotons.
Thanks Alfio, for looking it up.
On page 15 of the November 2001 issue of Scientific American,
under "News Scan" there appears:
"The attack on the World Trade Center unleashed nearly 1,700
tons worth of TNT. Average height of towers: 1,365 feet.
Total weight: 1.25 million tons. Collapse energy: 2x2^12 joules.
Equivalence to TNT: 500 tons. [Lee's note: I do not yet
understand why this does not contradict the first sentence,
but am rushing to correct my error.]. Energy in one gallon
of jet fuel: 135,000 btu. Maximum fuel capacity of a Boeing
767: 23,980 gallons. Approximate fuel detonated at impact:
3,000 gallons. Explosive energy, both planes: 9x10^11
joules. Equivalence to TNT: 990 tons.... Equivalent to TNT
of U.S. tactical nuclear warhead: 300 to 200,000 tons."
Mike and I were not so far off: we got 2700 tons of TNT, and this
says 1700 tons.
> One would wonder what a megaton-sized bomb would do to a modern city.
> Ciao,
> Alfio
I recall in the sixties we worried about a Russian 10 megaton hitting
an Air Force base 15 miles away, and we thought that our short-term
survival, at least, was impossible unless we happened to be hunkered
down when it hit. There are figures on radii of the fireball.
Lee
This archive was generated by hypermail 2.1.5 : Sat Nov 02 2002 - 09:17:31 MST