this post was submitted on 17 Dec 2024
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A train of 8000 tons at a velocity of 30 km/h roughly has the kinetic energy of 66.39 kg TNT.
Supposedly 100 kg TNT
~~I don't think your units make sense
kinetic energy has units of energy, but "kg TNT per second" is power (about 4MW). (I think just remove the "every second" and it's correct?)~~
Edit: parent edited comment.
You're right, but "every second" was meant more as a display of the energy in the train, like a large explosion "every second". Is that very wrong?
Hmmm, I'm not sure I understand...
A large explosion every second has units of power, not energy. So to me this is suggesting that the train is putting out power equal to its kinetic energy per second. That's certainly not the case
it implies that the train is powerful enough to accelerate to the speed in 1s, which is definitely not true.
But that's just my interpretation.
Yeah, I forgot that a large part of the energy is in inertia and not the pulling of the engine.
It seems to be a lot, how does it compare to an artillery shell? The tank doesn't look like it fared too badly.
Artillery shell with 1 kg of TNT has explosion energy of about 1 kg of TNT
Do they actually use TNT as the explosive though? I thought TNT was just the igniter for something more powerful like C4 or something.
I don't think TNT is used at all, I'm pretty sure it's some explosive compound, as you said. However, explosives are still measured in terms of TNT, called Net Explosive Weight (NEW).
For example, one pound of C4 has a NEW of about 1.25 pounds.
Looks like it's something like 6-12kg of net explosive content so if that's the same as NEW then it seems that the train has it beat by a fair margin, though I doubt the trains impact is as tightly targeted.