# 1,000,000 lbs of TNT

So I was watching this video of a nuclear-simulation using (supposedly) 1,000,000 lbs of TNT.

http://theync.com/video/m100306bomb.wmv

I was just wondering, anyone have any idea how much space that much TNT would take up?

Trinitrotoluene has a density of 1.654 g/cm3.

1,000,000 lbs of TNT would be about 455,000,000 grams.

That’s a cube that is approximate 6.5 meters (about 21 feet) on a side or a sphere 8 meters (about 26 feet) in diameter.

I hope I did that right.

I can’t tell you how big a pile of TNT that would be, but it’s interesting to compare that blast with a real nuclear explosion. The Baker shot in 1946 was only 21 KILOTONS – theoretically only one-fifth the size of the TNT explosion you linked to. But it’s clear from watching the Baker footage that the nuclear explosion is a far, far more destructive event. This suggests that the kiloton/megaton scale doesn’t really map well to actual amounts of conventional explosives.

I’m not gonna write it out but I did it twice and I got about 9,685 cubic feet. The cube root of that is 21 so I second the first guy.

Wait a minutePochacco, a million pounds is only half a kiloton. A kt is 1,000 tons and a ton is 2,000 pounds so there are only 500 tons.

21 Kilotons = 42,000,000 pounds

Witha density of 1.654 grams per cubic centimeter, I get about 270.86 cubic meters, or a cube about 6.47 meters on a side.

of course that with an 8-meter ball weighing a million pounds, you don’t even need to detonate it. You just roll it around and a lot of people is bound to get injured.

A cube less than 7 metres on a side? That’s a lot smaller than I expected. I mean…
<Dr. Evil> One. Million. Pounds! </Dr. Evil>
It just sounds so impressive!

I wonder how much it would cost.

Look at it this way: It would fill a 1000 ft[sup]2[/sup] room with a 10 foot ceiling.

Well, you can cram a 450 hp engine under the hood of a common sized car. Can you imagine what it would take to clean up after 450 horses? I don’t want that job.

Oh, duh. I read it as a million tons, not a million pounds.

Ignore me and carry on … .

Just to get things straight, 1,000,000 pounds = 500 short tons = 0.5 kilotons. So prontist’s video shows an explosion with the relatively small yield of 1/2 kiloton. I still wouldn’t want to be standing anywhere near ground zero though.

The Tsar Bomb, the most powerful nuclear device ever detonated, yielded about 50 megatons – the explosive force of 50 million tons of TNT.

No, nuclear yields are measured in metric tons. The US ton and metric tonne are almost the same, though. One million pounds is a bit shy of 454,000 kg or 0.454 kilotons.

My mistake. The three tons:

short ton (US): 2,000 pounds
long ton (UK): 2,240 pounds
metric ton: 1,000 kilograms (~2,205 pounds)

A useful comparison is the 100-Ton Test in May 1945, conducted as a trial run and calibration ahead of the Trinity Test.
This involved stacking crates of TNT in a rough cube atop a 20-foot high wooden tower until there was roughly 100 tons of it. In this photo of the completed stack it’s about twice the height of the person beside it.
For a sequence of colour photos of the resulting explosion, see this page.

How would you go about exploding a million pounds of TNT? Is it just as simple as sticking a detonator into the pile and igniting it, or would you need a more complicated setup to ensure uniform combustion?

The answer is, it depends. The shock wave will propagate spherically until it reaches the material boundary, at which point it will propagate with a constant curvature. Since shockwaves travel faster than the bulk speed of sound in the material, scattering the material due to blast pressure is not much of a problem. However, the more confined the energetic material is, the faster and more efficiently it will detonate. Several detonators placed symetrically throughout the entire mass, connected in parallel and fired at the same time would probably be the best option.