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Q & A: big booms

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Most recent answer: 10/22/2007
Q:
how many sticks of dynamite would it take to make the equivalent explosion of an atomic bomb. how many black cat fireworks would it take?
- Anthony
u of i, champaign
A:
Anthony- Obviously we can't give you an exact answer, because so far as we know there isn't a single standard size for dynamite sticks, and there certainly is a range of sizes for atom bombs. So I'll go through a very rough calculation.

Let's say a stick of dynamite weighs a couple of pounds. A good deal of that is inert matter. (I think it's diatomaceous earth- shells of little sea creatures.) Anyway, let's say that each stick has something like a pound of high explosive. A smallish atom bomb, like the one that destroyed Hiroshima, has the explosive power of some 15 kilotons of high explosive, or 30,000,000 pounds. So something like thirty million sticks should work fine, if you can figure out a way to make them all go off at once. Fortunately, this is difficult and expensive and detectable enough that we don't have to check into your security clearance before revealing this information.

By the way, a typical modern bomb in the U.S. arsenal has about 15 times more explosive power than that. The U.S. and Russia each have thousands on missiles pointed at each other. In response to the U.S. breaking out of the Anti-Ballistic Missile Treaty a few months ago, Russia announced it would feel free to keep its missiles on "launch on warning". The warning would come from reliable Russian technology. So that's an awful lot of sticks of dynamite that could go off any time.

On a lighter note, we don't really know how much explosive is in a black cat firework.

Mike W.

(published on 10/22/2007)

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