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Computers allow humans to make mistakes at the fastest speeds known, with the possible exception of tequila and handguns

Tequila and railguns.

Handguns are, like, so yesterday.

http://www.railgun.org/
No updates since 2002.

"Can this technology used for making weapons?"

For some strange reason, there's something | There
called a "lameness filter" that repeatedly | are
rejected all attempts to post this message | lots
the way I wanted it to appear and saying I | of
had too few characters per line and that I | technologies
needed to reduce the count of "junk" chars | that
per line in my post. Perhaps it's just me, | can
but I think that making me do something so | be
TOTALLY HOKEY as THIS, JUST so the post'll | used
appear the way I intended for it to appear | to
somehow seems MUCH more hokey, in the long | make
run... But maybe I'm just being too ornery | weapons...

You just have to learn to think like this guy
and turn yourself into a human one of these.

kinda like these people

is railgun.org

They have a detailed overview of the physics involved, too.

railgun [railgun.org].

So, take productive, tax paying, probably highly trained (computer geeks tend to be the biggest mp3 collectors) members out of your society, along with whatever money and goods they would be contributing back to the economy, and spend lots of additional money to store them in prision. Don't forget the fact that they will have a hell of a time finding work once they get out, couple that with the intensive criminal training they will receive by associating with known felons, and the end result is that you not only decimate your economy, but you breed a clan of highly intelligent uber criminals who would like nothing better but to run the state even further into the ground. Yeah, sounds like a plan. At least the RIAA will have enough money to hire 24/7 body guards to protect them when the world decends into anarchy... Well, at least until one of those newly trained bad guys gets his home made rail gun up and running...

If you want to know how to build a REAL railgun, try this. Admittedly, its a bit harder to build.

1) mean free path. something everyone forgets to consider is the mean free path. that's basically the mean distance between molecules under pressure (or vaccuum, as the case may be). plasmas have a certain sweet spot, where the mfp is just right, and it takes the least amount of energy possible to create or strike, and maintain that plasma. these conditions are probably not ideal at the leading edge of a wing at mach 1+. granted, these plasmas have been observed, and do exist, and really take no more energy to create that what's needed to fly the plane. however, say you do manage to pluck some of that plasma away and fire it off in some form. how are you going to sustain it? chris thomas has a good idea with firing a laser into the back end of the sonic cone, etc. i'm not gonna repeat it cuz it'd take too long to type. you get the point, creating it is easy, sustaining it is not.

2) why not figger out a way to harness some of the energy from a plasma (through rf inductance or whatever) and use it to power a capacitor bank and make that semi-portable railgun? after all, what's a plasma anyway but a big ol' bundle of free floating radicals with a lot of energy. the problem with railguns is the power supply. we can't exactly load up an f-16 with a big battery bank. the thing would be harder to fly than a b-52. sucking the power off the engine isn't ideal, because that power's needed to power stuff like the flight control systems and whatnot. stuff you don't really want connected to a big bank of capacitors, stuff you don't want subjected to power spikes and drops every time you need to fire off a shot.

3) towards the bottom of the article they talk about shiva star and storing up 10MJ of energy in caps and releasing it instantly. they don't talk about how long it took to charge up those capacitor banks. they also don't talk about the massive copper rails needed to link the caps. take a look at the tabletop railgun projects, like railgun.org. those are small cap banks, storing up a couple thousand joules.

i'm rambling and i've derailed my train of thought. i'm gonna go now and appear like i'm actually contributing something useful to my workday.

A railgun consists of two parallel conductors, the "rails," bridged by a non-ferromagnetic conducting armature. The railgun is fired by creating a current loop that flows from some large power source, down one rail, across the slug, and back up the other rail. This current loop induces an enormous magnetic field which, in turn, pushes the armature down the rails with a force proportional to the magnitude of the current, the separation distance of the rails, and the magnetic field.

So, while the projectile is propelled by a magnetic field in both cases, a "rail" gun uses a specific method (rails+ conductive armature) to generate the field. For more information see railgun.org