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by JofArnold 5524 days ago
Or to look at it another way:

v^2 = u^2 + 2as = 0 + 2 x 9.81 x 2,000 = 39,000

KE = 0.5mv^2 = 0.5 * 300 * 39,000 = 6MJ

I.e. about 1kg of TNT. "Crush"?? I'm with you on this one, mmaunder

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For another comparison, modern KE sabot anti-tank rounds (what tanks shoot at other tanks) use penetrators weighing from 4 to 8kg, with a muzzle velocity of around 1500m/s, giving a low of end of ~9MJ. Granted, this is ignoring air friction, and must punch through the front armor (much much thicker) than the top armor that bombs go through.

Also... as a cost comparison, JDAM (the US GPS guidance) kits cost 20-30k per kit (you strap them onto 'dumb' bombs). For the actual bomb itself, you're talking on the range of a buck or two per pound... the inert training versions are much cheaper than that. Explosives are cheeapp. Silicon is pricey.

See link below for pricing information! (The Mk-84 is the 2000lb 'dumb' bomb, it's listed along with its training/concrete version).

http://www.fas.org/man/dod-101/usaf/docs/munition-cost-11-1....

Just a thought, but if the silicon is expensive, could you potentially engineer the majority of the computerized parts into a UAV that could detach at the last moment and fly back?