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by lobster_johnson 3671 days ago
The destructive power of this gun comes from the energy of its momentum (mass x velocity) -- all the energy expended to accelerate it needs to go somewhere when it reaches its target. Same principle as a handgun. The difference is in how the projectile is accelerated.
2 comments

The destructive power of this gun comes from the energy of its momentum

Sorry, but it sounds like not all readers on this website know the difference between kinetic energy and momentum. Here's a K-12 level website: http://www.batesville.k12.in.us/physics/phynet/mechanics/ene...

It has a very illustrative question: Would you rather be hit by a 1000 kg vehicle going 1 meters per second, or by a 1 kg meatball going 1000 meters per second?

Not sure why you're replying to me. I literally referred to kinetic energy ("the energy expended to accelerate it") in my comment.
Your comment seems to be confusing momentum (m * v) and kinetic energy (m * v * v).
I'm not confusing anything, but I wasn't trying to be scientifially rigorous, either. By "energy of the momentum" I was referring, admittedly imprecisely, to the fact that the kinetic energy is a function of the momentum. Or, to be precise, E_k=p^2/2m. At least as I understand it.
> the energy of its momentum

Huh? Energy and momentum are two _different_ quantities related to the movement of an object. I was talking about using the energy _instead_ of the momentum as an indicator of damage.