TechStuff Classic: TechStuff Plays with Plasma

So this one was originally published on February two thousand twelve, is called tech Stuff Plays with Plasma and Chris Palette and I end up talking about plasma and how it works in technological applications. Enjoy courtesy of a little Facebook feedback you be and this comes to us from our friend Basu, who says, hey, Jonathan, our plasma ray guns possible. I'm waiting for the next podcast on this. Well, here's

our next podcast on plasma reyguns. But before we get into the idea of weaponizing plasma, let's talk a bit about what plasma is and maybe some common or at least more realistic applications for plasma that that we use today. Okay, So, so plasma it is the fourth state of matter. Yeah, it's funny to me because growing up, um, perhaps my my school system was narrow minded, although I don't think so.

We we learned about solids, liquids, and gases. Those were the three states of matter and that's all there were. And the Brontosaurus was a dinosaur exactly. You know, it's probably because I would guess it's probably more because growing up, plasma is a little hard to grasp. It's I figured out. Literally, I figured out, yes, because if we did heard it hurts. Uh. I'll the way I figure the best explanation would be

look at it from the stance of molecular movement. Okay, So with solids, the solids are made up of molecules, and those molecules don't move a lot. They are moving. So even in that granite table that you might see that the molecules within that granite table are actually in motion. They're just not moving a lot. You can take it for granite that they'll stay put. Yes, And then in liquids you have a little more molecular movement, and the

the actual composition of the matter it acts differently. Right, So ice is a solid, water is a liquid, and then if you add more energy into the system and you create more molecular movement. You can make that liquid turn into a gas, and then gas, you've got a lot more molecular movement. The molecules aren't as packed closely as close together as it would be in a liquid or in a solid, and that's when you've got the

gas form. Well, plasma is the next step. It's when you've added even more energy into that that element, and this also tends to strip away electrons ionizing that gas. So you've got free electrons flowing through the gas that an ionized gas, that is plasma. So in a way, you can think of plasma is sort of a subset of gas, but it's really its own thing because it's an ionized gas. Jonathan, it strips away electrons. Are you sure well? It pushes electrons way out into the outer shells.

I was. I was going for the joke there they lose electrons. Are you sure? I'm positive? Okay? No. The reason why I said that is because literally this week phil Plate, the Bad Astronomer, wrote a post about ionizing atmosphere conditions and how that creates are the auroras to the Aurora borealis and the aurora estrallis, and he had written about how it strips electrons away from oxygen and then later corrected himself saying, all right, technically that is

not correct. What really happens is that the electrons are pushed to the further energy shells around the nucleus of the atom, and when the electrons come back down to their natural energy shell, photons are released. And that's the aurora. So that's why I wanted to not do the I'm positive off the bat okay okay, Um, you can tell

we don't we We sort of prepare, but we don't rehearse. Um. It's funny too, that that we think about plasmas being the fourth state of matter and the way it's uh kind of strange because um plasma is far more prevalent in our universe, most plentiful state of matter, of all matter in the universe, all anything that's not dark matter, whether or not that exists isn't isn't totally different subject matter, but it's really too many matters. But yes, of all

the matter that we have observed, plasma makes up. And you might think, well, that's weird, because everything I encounter tends to be either a solid liquid or a gas. I very rarely encounter plasma. Well, that's because you don't live on the Sun. I have encountered a couple of people who have encountered plasma firsthand, um, more than once, because they have been hit by lightning. Yes, and that's what I was saying with my quote at the beginning

of the show. Lightning is something that can create plasmas. One of the ways that we can find naturally occurring plasma on Earth. The plasma does not last very long. Um. But we'll get into that in a second, and I would avoid coming into contact with plasma as often as possible. Now, there are other plasmas that we encounter. Anything, any sort of ionized gas is a plasma. There's some that are

considered cold plasmas. And by cold, we're talking in terms of relativity here, right, you know, it's just it's colder than say the plasma you would find shooting out of the sun. And then they're blood plasma, right, which is totally different, not the same stuff, but like a neon sign, that's that's an ionized gas within the k neon is

ionized within that sign. That technically is a plasma. It is just not the same quite quite the same thing is what we would find, say a plasma cutter, which is kind of what I wanted to talk about, because plasma cutter, that's something that's it's a tool that we use that can cut through really sturdy, thick sheets of metal.

And it's really impressive if you ever see one of these in action, because you might look at a sheet of metal and you think that, how the heck are you supposed to shape this so that you can use it in various applications like building airplanes. In fact, building airplanes is kind of where the idea for plasma cutters came into play. Yes, that's that's true. And they plasma cutters not only cut through metal, they do it like butter. Yeah,

like butter. I'll give you a topic. Plasma plasma cutters are are really, if you'll pardon my again over simplification, really really fancy because not only are they cutting their cutting very precisely and they tend to uh basically the way they cut through it, they do it uh in a temperature so hot that it it steals off the metal and prevents corrosion. Yes, um, but again that's an oversimplification.

Let's get into what's really going on here. Sure, so back during World War Two, there was a demand for building aircraft very very very quickly. Yes, and that's that's kind of a problem because aircraft are very complex, very large devices. So that meant that, you know, you had to find a new way to go into mass production. And so there were different experiments being done about new

means of welding materials together. And uh, some folks discovered that if they used a gas and inert gas fed through an electric arc, so they create an electric arc between a couple of electrodes and they shoot gas through that arc, that they could create a very effective welding tool. Now, um, so that was sort of the basis of the plasma cutter. Now this was not used to cut. This was used to weld, so welding different sheets of metal together, yes, exactly. So, uh,

but that that started the foundation. What happened was in the nineteen sixties some engineers figured out that they could actually increase the temperatures of this this uh, this plasma by speeding up the flow of gas and by controlling the diameter of the nozzle. So if they decrease the diameter, they're they're making it, you know, narrower, and they're increasing the flow of gas and they're pushing it through this electrode. It would actually increase the temperature quite a few orders

of magnitude. And this is where the idea of using this to cut through metals started to come into play. And uh, technically, the typical plasma cutter uses the sheet of metal that it's cutting as part of a circuit. So you've got to think about the parts of a of a plasma cutter. You've got an electrode inside of it, that's what that's what's providing the the the charge. You've got the cutting gas that is inside of it. This is the the inert gas that's going to be passed

through this electric charge and superheated to plasma. And then you've got a controlling gas that's around that that actually is used to help concentrate the flow of the cutting gas. It's it's so you've got the nozzle that's helping concentrate the flow, and if you've got a second gas that's also sort of pushing against that cutting gas, keeping it nice and tight. And then once you put the the plasma cutter against the piece of metal, then that creates

a circuit. The shock from or the charge from the electrode goes to the metal. The metal has sort of a positive charge to it the and and we know that the negative wants to go to positive, so the electricity hits the metal. The gas flowing through the nozzle is ionized, becomes plasma and superheats and actually turns metal into into molten material at the blink of an eye. And that's when you can just start cutting through it

like it was as Chris said. But yeah, when you're reaching temperatures of thirty degrees fahreneit that's se degrees celsius. That's pretty hot. And when we're talking about increasing the flow of the gas, we're talking this this gas is flowing at a rate of around twenty thousand feet per second. Know how many meters per second? That is courting on my fingers about six someone's been reading how stuff works

dot com. Excellent article. We do have an article on how plasma cutters work at how stuff works dot com, which is it's a good thing to read about. And if any of this sounds familiar to you, guys, then you've been listening to tech stuff for a really long time, because we did do an episode ages ago about plasma waste converters and what a plasma waste converter is. It's

a really cool application of this technology. It's essentially using a device similar to a plasma cutter, a plasma torch to create this incredibly super hot ionized gas in order to liquefy or gasify trash. So, depending upon what the trash is made out of, it will either turn into a gas because you know what's the plasma is applied to it, or it will liquefy. Uh So essentially car

carbon based uh lment. It's anything that's carbon based within the trash is going to gasify, uh and everything else liquefies and um it's you can use that gas depending on on what you're producing. You can actually use that gas as fuel, and the liquefied stuff, once it cools,

turns into stuff that looks kind of like obsidian. In fact, I have I haven't a sample of that because when I did the article, I visited a engineer at Georgia Tech who gave me a sample of this solidified waste which looked like it was a volcano rock, which essentially is what it is kind of so anyway, that's another interesting use of plasma technology. Chris and I will continue our discussion about plasma in just a moment, but first

let's take a quick break to thank our sponsor. Now let's kind of talk a little bit about the concept of plasma weapons. So we had our our listeners specifically asked us, like our plasma ray guns possible? Um In a word, no, at least not without today's technology. And there are a lot of different reasons for this. One of those is that um plasma, if you were to generate plasma at a at a temperature that would be considered weaponized. So we're talking about you know, hot hot

plasma UM. You have the problem of heat dispersing too quickly, so the the ionized gas would lose a lot of energy as soon as it leaves wherever wherever you're generating it. Right, so at the point of generation, it's going to be very, very hot. So if I were point blank right up against you and I pushed a weapon against you and I pulled the trigger, then yeah, you're gonna get cut

in half, or you're gonna have a whole drilled through you. Essentially, But if you're you know, twenty feet away, this ionized gas is gonna be losing energy at a very fast rate, and as it loses energy, it's going to revert back to a regular gas, and you can't really get it to travel very far. And it also disperses. So if you were to have this ionized gas come out of the end of a ray gun, it's not gonna be a ray or a beam, right, It's not gonna move

forward in a concentrated beam. It's going to disperse hour it's gonna bloom. So in that sense, you also don't really have much of a weapon because the further away the person is, it's it's just like a shotgun in a way. You know, a shotgun shoots shot and that shot spreads as it goes out, So the further away someone is, the less concentrated the impact will be right, right, So, same sort of thing, except even on a bigger scale, because we're talking about individual atoms here, not just uh shot,

And so that's another problem. Um, there are various ways of getting around this. If you had a gun that somehow could create an electrical charge all the way down to wherever your target is, it could ionize the gas immediately around the electrode. But in that case you're talking

about some sort of superpowered taser. Yeah. Now, if you'll remember, if you think of it as as the plasma cutter, you'll remember that in our discussion on how it worked, just a moment ago, UM Jonathan was pointing out that the metal that's being cut requires uh IS is basically charged. It's part, it becomes part of the circuit. So if you were shooting at something five feet away, for example, UM, it's going to be very difficult. I mean, you can't.

You have no circuit. You can't you don't have a circuit. UM. Also, you'll remember that Jonathan was talking about the gas that's on the outside of the pressurized gas that is used to cut UM, that's controlling the the cutting of the plasma cutter. Without that UM, it's exactly what Jonathan says, you don't have a real way to control it. And you might say, well what about lightning, Well, lightning it

forks it's not controlled. UM. So yes, lightning can can travel a long distance, but it also it's a charge. We know that the ground and the clouds are charged differently. Essentially a circuit. It's certually the only last a moment. But you know it's not so if you had if you somehow arranged it so that everyone on the enemy's side war of particular suit that should positively charged clothing, so that I could use this negatively charged electra to create a circuit between me and you that I can

vaporize you, that would be great. M So, yeah, that's a little tricky. Um. Yeah, there are a lot of other issues with this, but there that's not the only way to weaponize plasma. That's you know, that's if you were to have a gun, like in the Halo universe. In the Halo University, aliens have plasma weapons and they shoot these kind of blobs of energy, which you know, essentially it's like uh, blobs of of superheated gas and they travel as if it were a solid projectile and

uh it's like little sunlits. Yeah, these little energy weapons that can do massive amounts of damage, particularly literally to your shields, right against shields. So yeah, supercharger plasma pistol and then immediately switched to your regular pistol. It's in a great way of anyway. So that's just not viable right now. The equipment we would need to create plasma is much larger than what you could have in a handheld gun, and you just wouldn't have those results. But

that's not the only way. There are other ways. Like there's an example, there's a weapon that's been worked on by the US government over the last few years called a pulsed energy projectile weapon or PEP. Now, this creates a it uses it uses a very high powered um laser style weapon. So it's not a plasma weapon at its at its source, right, it's just create it's just firing off energy. It's an energy weapon. And the idea is that when the energy contacts something solid, then it

creates a plasma. It actually excites the material that it contacts with and that's what creates the plasma. So the plasma is not contained within the weapon. UH and it's it's just it generates as soon as the ray hits something solid and then at that point what happens is the plasma that's generated quickly starts to expand because the

energy from the ray is continuing to hit it. Okay, So that expanding plasma creates an electromagnetic magnetic pulse, and this pulse is geared to UH kind of short circuit our pain receptors, and the idea is that this weapon would either or paralyze you. It would just make all you know, your muscles contract kind of like a massive taser, or would paralyze you with pain. You would feel so much pain you would be incapable of doing anything else.

This is the pain ray that people have talked about, and UH there's a lot of concern in the international community that such a device would be used not to stop a riot, but rather as a divisive torture, to to really torture a person if you were trying to interrogate them. And of course the whole torture thing has its own issues beyond just the technical but that is a way that people are weaponizing Plasma's just not using plasma as a direct weapon. It's just part of the weapon.

We have a few more points to make about plasma before it's all said and done, but before we get to that, let's take another quick break to thank our sponsor.

There are ideas of creating UH plasma to act as an antenna because they can be much more efficient than metal antennas, and or even use them in anti missile systems where the idea would be that if you had missiles coming in, you could fire beams up into the upper atmosphere ionized part of the upper atmosphere so that when missiles were passing through them, they would detonate and not land and hit you. Um. So those are ways of weaponizing plasma. That's not not quite the same as

having a a cool ray gun. You know, you're Q thirty five space modulator or whatever it's called. I'm sure, I'm sure someone's gonna write in so they know it was a Q thirty two space modulator. Sorry, that was the obsolete person I thought I've upgraded. Yeah, it's also hard to imagine something that shot plasma that would, you know, stop at a certain person. It would, it would shoot through schools, it would see really it would, yeah, if

it if it were really a superheated gas um. Yeah, I mean, if you were to find some way to control it so that it maintained its integrity and could travel best distances, then what would stop it from shooting through whatever it was you hit and then going moving on. I mean, it would lose energy every time it contests. But if you're talking about superheated, if you're talking about

temperatures that that rival the temperature of the sun. Um, it's gonna take a while for that to to lose enough energy for it to If you could keep it concentrated like that, it would take a while for it to lose enough energy for it to stop. Which just reminds me of the documentary Real Genius where they fire off the laser and it goes all the way through the entire laboratory and shoots through the head of a statue on the quad. Yeah. So anyway, Yeah, that's that's

the basis for the whole idea about plasma weapons. I think I'm not going to go so far as to say they're impossible. It's just that with today's technology they are not really possible, And it may be that they could be possible but not practical. Yeah, it'll it may very well be that by the time we could create a plasma weapon, something even scarier is out there. So um, yeah, it'll be interesting to see if there's there are further

developments in attempting to weaponize plasma technology. But really, when it comes down to it, it's very useful tech for things in manufacturing and and like I said, waste management or potentially in waste management. There are very few plasma waste converter facilities out there. There are only only a couple in the United States, and there are a few in Japan and UH and that's about it. But but they have the potential to really change the way we

deal with waste. I mean they could. They could actually help reduce landfills because most of them have capacity so great that they would be able to serve not just the community on a daily basis, but also take uh garbage that has already been dumped in the landfill and start using that as well. So every day it would be using a little bit more of the landfill as well as taking care of all the daily trash that was generated by the population, plus possibly creating energy as

a result through uh through using fuel. Um. You know, it's a it's an attractive prospect, but it also requires quite a bit of an initial investment. So anyway, this look is going to be a short episode. So hey, guys, UH you're welcome. I hope you guys enjoyed that episode about plasma. It's always fun to revisit these old topics that Chris and I did back when we were young and naive and only had a vague notion of what podcasting was all about, whereas now I have a slightly

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