Stuff You Should Know - How Magnets Work

Episode Date: April 23, 2013

You can stick them to the fridge or use them to transpose sound to tape, whatever they are used for magnets are surprisingly interesting. And knowing just exactly how and why magnets work will make you more interesting, which is why you should listen to this episode of SYSK. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

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Welcome to Stuff You Should Know from HowStuffWorks.com Hey, and welcome to the podcast. I'm Josh Clark with Guess Who. Tell them who I'm with, Chuck. Oh, Chuck. I'm with Chuck and Jerry's in the room as well. And since the three of us are together in this room, we have the podcast. I am so excited about this podcast. I knew you would be.

So much so that I'm worried about it because as you know, and anybody who even occasionally listens to this stuff you should know is aware of, the more excited I get about a topic, the poorer job I do at explaining it. Yeah. See, I already did it. I already said the poorer the job I do. Yeah. It's true.

So I'm just going to try to remain calm. Because all we're talking about is magnets after all, you know. And that's the way I feel. We usually balance each other out nicely like that. But you don't think that there is a certain cachet to walking around understanding how a magnet works. Do you realize what percentage of the population you're a member of for knowing that? Maybe.

Well, this is a guess, like 0.0029% of the human population knows how magnets work. I don't know anybody else until we selected this and started reading it besides Tracy Wilson who knew how magnets work. I think you are underestimating the curiosity of the general public for people to look up this stuff on their own. All right. I would like to hear from people if you already knew how magnets work. You act like if we don't tell people this and they're just dummies walking around.

I don't think that. That's not at all what I think. But we'll get corrections on this and I think that will prove that people know this and more. Okay. If you're a physicist whose specialty is the electromagnetic power. Yeah. They're cracking their knuckles right now and listening.

Right. Then yes, we're going to mess things up. It's true. But we have a general good, well, I'd say fairly detailed idea of why magnets exist. That's right. And we're going to explain that to everybody. But not in any way, shape, or form in a condescending manner. No, no, no, no.

Because all we did was research. That's right. It's not like we're making magnets here. No. We're just talking about them. You know they discovered these in Magnesia and Greece. Did you know that? What?

Magnets. Like natural magnets. Yeah. Like lodestone. Yeah. In Magnesia and Greece. Is that really a place? Yeah.

Magnesia. Yeah. Absolutely. You're not pulling my leg. Nope. Okay. But it was lodestone, a type of magnetite? Yeah.

It was magnetite. Because that's the strongest naturally occurring magnet, right? Like you can attract a paperclip just with this rock. That's pretty cool. Yeah, it is. Even cooler though are the ones that humans have conquered and mastered and own. That's right. Because all the magnets you come in contact with on a daily basis, maybe a weekly basis,

have been manipulated by humanity. See, I never come into contact with magnets. You know something? It's hard to find a decent magnet these days in an average store. Like you have to mail off for them. Oh yeah? Yeah. And I don't have refrigerator magnets because the stainless steel fridges, you can't put

a magnet on them. That's so weird. You can put it on the side. Yeah. So we have a few, you get magnets over the course of your life, whether it's like the pizza delivery guy has a, like we have one in the shape of a pizza slice with their number on it. You do.

And that's on the side. And like our vet, like we have a vet magnet. And this shape of a pizza slice is the number, right? And then like, you know, random people have given me magnets here and there, which I'll throw up there on the side. That's good. Those are nice mementos. You mean like those sometimes.

We got one of them on. You did? Yeah. That's nice. That's great Chuck. I don't have a lot of magnets or experience with magnets, but I understand them now. Now that you say that, I realize that I have more experience than I realized with magnets because we really, you mean I do have a pretty good magnet collection on our fridge.

But yeah, it is, it always struck me as weird that like stainless steel wouldn't, you couldn't put a magnet on that. Yeah. Now I understand why. Stainless steel is not a ferrous metal. That's right. You have to have a ferrous metal like something, say iron, nickel, cobalt, aluminum even? Oh really?

I think so because there's a type of magnet called the El Nico magnet and that's aluminum nickel cobalt alloy. Yeah. If you've got a really good guitar amp, you might have an El Nico speaker. Is that right? Yeah. They're pricey. Oh yeah, I can imagine.

Like you can buy the speaker separately and like switch it out in your amp to make your amp sound better, which I have been meaning to do for years but they're just kind of pricey. It's like 400 bucks just for the speaker. But how's the sound? Well, I'm told it's great but music guys hear much more than I do. Like real, real music guys, they're like, can't you hear the difference? And I'll be like, yeah, sort of. Are these music guys also El Nico speaker salesmen?

Yeah, probably so. All right, so let's get, so this is what I like about this article. It goes like basic to specific. Yes. You can start with the basics about magnets. They attract specific metals. As we've said, typically Ferris metals. Yes.

They have a north and south pole. All magnets do. There's no north and east pole magnet. Yeah. And the earth is the biggest magnet of all, I guess. It is. At least on earth. Opposite poles attract one another.

Like poles repel one another. They hate each other. That's right. Magnetic and electrical fields are related and we're going to explain why. I'm so excited and magnetism. I think I said electromagnetism earlier, so you can put your email away because I'm correct in myself. Yes.

Is one of the four fundamental forces of the universe, right? That's right. With gravity and the strong and weak nuclear forces. That's right. That's magnets. That's a great intro. Magnets, the object itself or a magnet is an object in itself that produces a magnetic field and it's going to attract, like you said, ferrous metals.

There can be permanent magnets, a.k.a. hard magnets, and they always have a magnetic field going and then you have the temporary magnets, a.k.a. soft magnets. They just produce a magnetic field when they're in the presence of a magnetic field and only for a short time and then for a little bit thereafter, like once it's gone. And then electromagnets, when you apply an electrical current to some magnets, they become magnetic. That's right. And if you have a doorbell, you probably have an electromagnet in your house.

Yeah, the doorbell. Yeah. I looked it up. It's more complicated than you would think. Oh, yeah. I don't have a doorbell. It's like a Rube Goldberg-esque contraption that is apparently pretty standard and uses electromagnets.

It's neat. And actually, if you're interested in that, there's an article, How Doorbells Work on HowStuffWorks.com. Yeah, isn't it weird that the doorbell, or maybe it's just me as a miss-and-throw, but like the sound of a doorbell now is not like, oh, I wonder who's here. It's crap who's here. Right. Because no one just drops by anymore.

Right. Either that or like they know. Yeah. Yeah. Yeah. So Chuck, the magnets that you typically have like your pizza boy magnet or like the circle ones are probably the best example. Just a ring, that magnetic ring that you see and grew up with, those are a specific type

and they're called ceramic magnets. That's right. And they're probably the weakest magnets commercially available except for the pizza slice ones. Right. Because that's almost like a sticker. Yeah. I mean, it's connected to, or it's got a topper on it with printing.

Yeah. A topper. That's the word for it. There's a word I could find. The topper. Yeah. A slice topper. But with the ceramic magnet, it's magnetic material mixed with ceramics and it kind of

cuts it and it makes it a little weak. Yeah. But good enough to stick on a fridge, which is all you're looking for. Yeah. And it's cheap. Very cheap. You already mentioned the Alnico magnets, which are more expensive. And like you said, aluminum, nickel and cobalt and they are stronger than ceramic, obviously,

but not as strong as the ones we're about to talk about like neodymium magnets. Yeah. Or samarium. Samarium. You've got to be kidding. Samarium. Okay. Samarium.

Both of those magnets incorporate rare earth metals, which are extremely magnetic. Or when combined in an alloy, it can be very magnetic. That's true. And now they even have, and this is something I never knew. They have plastic magnets called magnetic polymers, and I guess those are for use in just very certain applications, like cold temperature applications. Yeah. Or maybe that's what's on your pizza slice magnet.

Or it says they pick up only very lightweight things like iron fillings. So I wonder if that's what you use with like your, you remember the little toy kids thing where you could have a guy's face and have the little iron fillings and you could move it around and make a beard or mustache or whatever. Sure. I bet that's what that is. What was that called? I don't know.

Old timey toy number 273. Not an Etch-a-Sketch, not a Hugo, something like that. And why was it that anybody who had a beard from the 1940s to the 1960s, any child's toy, was like the most disturbing looking creature you could come up with? You think? Oh yeah. Have you ever heard of Rushdind dolls? No.

They were this very successful toy company and they came out with a line of hobo dolls that were like the scariest things you've ever seen in your life. Of course. Like they were meant to damage children, obviously. Oh, keep them from hopping trains, probably. I guess. Yeah. Play with it at home.

This is what happens. Don't go out on the road. Yeah. If you hop trains. Interesting. Let's see. Oh, I made a blog post actually called 27 of the most unintentionally terrifying dolls you've ever seen or ever created.

That's like almost every doll in my opinion. You should see this slideshow. It's pretty good. I'll check it out. Okay. So let's talk about making magnets, Chuckers. All right. Well, you talked about lodestone, a form of magnetite, and that is the natural, strongest

natural magnet. Right. You don't have to do anything to it. So I guess the discovery of lodestone and the fact that it attracted metals made people start to tinker around with it. And I guess around the 12th century, people figured out that if you took a little iron pin and you took some lodestone and you petted it in the same direction, preferably in a northern direction, you could magnetize that iron filling.

And if you suspended it in something like water in a leaf for anyone who's seen that movie with Alec Baldwin and Anthony Hopkins, The Edge, they magnetized like a needle and put it in like a water-filled leaf, and they figure out which way is north. I knew I'd seen that before. So that's basically magnetizing a pin using lodestone. That's how the earliest compasses were made. Very cool. Yeah.

So what's going on here, and this is sort of the basis, and we'll break it down to, like you said, a more molecular level. But what's going on here is something known as a region called a magnetic domain. And it is actually part of the physical structure of any ferromagnetic material. So we're talking, again, iron, cobalt, and nickel largely. And each one is like its own tiny little magnet. Right there, it's got its own little north pole, its own little south pole. And if it's un-magnetized, then this stuff is just going to be random and pointing in

all different directions. Right. The domain has its own north and south pole, but it's not necessarily aligned with the north and south pole on earth. Right, they're just kind of a skew. If it's magnetized, they're all pointing in the same direction. Right. Yes, that's pretty much all you have to do is figure out how to get all of those magnetic

domains to align in the same north-south line. Yeah, because if they're not, they're just canceling each other out. Exactly. So the more domains that you have pointing in the same direction, the more powerful magnet you have. And in each of these little domains, you can just kind of, I almost see it as like a little pocket in the molecular makeup of this, like an iron, the north pole of one domain flows into the south pole of the domain in front of it, if they're all aligned.

Yeah. And you add a bunch of these up, they produce one large magnetic field for the magnet as a whole. Yeah. Right? Yeah, which explains why if you do the old trick in elementary school where you bring one magnet close to the other, one, it'll either repel it or snap it together like one larger magnet.

Right. Because the force, this magnetic force is going into, out of the north pole of the magnet, and into the south pole of the magnet in front of it. There's nothing very dirty about that. It is. Right. Or if you take the north pole of one magnet, north pole of another magnet and put them together, they repel one another because their magnetic forces are flowing in opposite

directions and pushing one another apart, which is kind of funny because this is how magnets work, but it bears such a striking resemblance to, like, something they would have come up with in the 15th century, like the force flowing out. Yeah, this invisible force. Right. It's witchery, and this is why magnets won't be brought together. Like people would come and drag us out of here and toss us in a lake to see if we float that.

Exactly. So we could stop there, and you would have a pretty good idea of things, but we won't. No. We'll continue on. Okay. We'll go a little more in detail, huh? That's right. If you want to make a magnet, you have to get all these magnetic domains flowing in the

same direction, just like we were talking about earlier when you rub the needle on the magnet. You expose it to this magnetic field, and we get these suckers to align in the same way, and then boom, that is one way that you can get a magnet. Right. And there's different ways of doing this. You place it in a magnetic field in the north-south direction. You can hold it in north-south direction and hit it with the hammer. Yeah, that's crazy.

It is a little crazy. Like you're physically jarring these domains into alignment. They're like, huh? Yeah. Okay. I'll point this way then. Or you can pass an electrical current through it. That's kind of a cheat.

And they think that this is where a lodestone came from. Either it was when this rock formed, the magnetite formed from a lava, it was aligned with the north-south pole of the earth, so it became magnetized. Or it was struck by lightning, so an electrical current passed through it. That'd be pretty cool. And it became magnetized as a result. That seems likely. Right.

But today, the most common method of making magnets is to place them in a very strong magnetic field, and by the boom, by the bing, their domains start to wind up. Yeah. There's going to be a little delay though. Yeah. And I saw this on a YouTube video of this guy. There's a really good one. I don't know what it was called, where the guy broke it down.

Whenever it's stuff I don't understand, I always type kid science, and then I look and see what videos are available. Yeah. Yeah. No, it's good. It really helps out. Yeah. But there will be a delay called hysteresis, or hysteresis, and that's basically just

the time it takes for the field to change direction and all align itself. Right. Because when you get these domains going, the ones that aren't already lined up on a north-south pole, they just rotate around and do a little crazy spinning until they land on it. And the ones that are already aligned north-south, they grow bigger. Yeah. Become more robust, I guess.

Yeah. And as a result, other ones, the walls between smaller domains will shrink, and so you have large north-south domains, and then even the smaller ones are now probably polarized along that north-south line, and you have just created a magnet. Yeah. And here's what I think is one of the really cooler aspects of this is how strong your magnet is depends on how hard it was to get these domains to move in that direction. And the harder it is, the longer it will stay magnetized, which sort of makes sense.

It's almost like that. It was so stubborn to get going, but then once you got it going in the right direction, it was then stubborn, undoing it, that action. Right, which kind of makes you wonder, like, if over enough of a time span, will any magnetized material eventually lose its magnetism? Oh, just left alone? Yeah. Huh.

That's a good question. There are things you can do to demagnetize things. You could take a magnet and put it in a magnetic field that's polarized the opposite direction. Yeah. That's kind of mean. You can boil it alive, which is also very mean, and heat it to the point where it loses its magnetism. Yeah.

The Curie point. The guy in the video tested this. He had a paper clip on a string tied to the table, and then the magnet was like a foot off, so it was just, like, thwing, and then he took a... Was it a Jerry Lewis magnet? And then he said, Dean, bring me a lighter. And he got a lighter and heated up the paper clip, and you see it start to shake, and then eventually it just poop fell.

That is a weird story. He demagnetized it. Yeah, he did. Using the Curie point. So okay, again, we could stop here. I think everybody understands how magnets work, right? Like there's little magnetic domains that are in all kinds of crazy directions, and then when you expose them to a magnetic field, they line up together, and they produce their

own magnetic field around that magnetic material. And then there you go. It flows out of the north and into the south. Magnets, right? I would like to see a survey. I wish you could take an instant survey of people that, you know, half of them are going, go, go, go, and half of them are like, I'm good. That's all I need to know about magnets, you know?

I think our listeners are pretty curious folk. Okay, so we're going deeper, and Tracy Wilson, who our site manager here, of Stuff You Miss in History class now, she wrote this one, and she's so thorough. She has a very nice little pun in this section called Shipping Magnets. Get it? Shipping magnet? Yeah, I got it now. I didn't notice that before.

Yeah, it's a pun. What she's talking about in this section though is interesting in that very large magnets present a lot of problems because they're super strong, and you can't just throw it on a truck and, you know, drive it across country, you know, it'll disrupt everything. So very specific precautions have to be taken when delivering large magnets used for certain, like, industrial applications, one of which is they have machines that, because it'll pick up all this ferrous material along the way. Right.

They have machines when they get there to remove all that stuff. Yeah, and I mean, imagine if you're shipping it in like a truck, and the truck has some sort of iron alloy in it, and you have a huge industrial magnet, how are you going to get that off of the truck? You're not. Exactly. So they magnetize these materials on site, typically, right? Oh, is that what they do?

That's what I understand. Oh, okay. Or else they just rely almost exclusively on electromagnets, which become magnetic when you pass a current through them. Yeah, I think it's a manpower. Right. Give me those tin guys. American ingenuity.

That's how you do it. Pull! It sucks, sir. Right. Well, speaking of sticking, we're going to break it down to the electrons, which... The atomic level. This is bound to happen. Yeah.

Because that's really where it all starts. Well, I was just saying, like, electromagnets, they become magnetic when you pass a field of electricity through them. Yeah. Or a current. And all electrical current is a flow of electrons. Yeah. It produces electrons, produces electricity, and electricity and magnetism are very much

related. And this is why. Because on the atomic level of a ferrous material, iron, nickel, cobalt, right? Yeah. These are the big ones. It's called the big three. Well, let's talk specifically about iron. Okay.

In an iron atom, there are, around its orbit, in its orbit, there are electrons moving around. Yeah, would they spin downward or upward? And typically, they're paired. And when you have a pair of electrons, one spinning upward, one spinning downward, they're never any other way. There's no pair of electrons that both spin in the same direction. It's always opposite. Yeah.

And it's called the poly exclusion principle. Yeah. It's just not possible. Right. Exactly. So, in iron, you also have four unpaired electrons that all spin the same way. Now, those ones that are paired and spinning the opposite direction, they cancel one another out.

Yeah. But these four spinning the same way produce a magnetic field, a very, very, very, very tiny magnetic field, but a magnetic field nonetheless. Yeah. Right? And this is very unusual for these unpaired electrons to be spinning in the same direction. That's why it only happens in things like iron, cobalt, and nickel. Right, exactly.

That's what makes them ferromagnetic materials. Yeah. Potentially magnetic because they have these unpaired electrons that are spinning in a certain direction. Right? That's right. And then because these things are spinning in the same direction, they attract other atoms to kind of line up that are spinning in the same direction to line up nearby.

And then those create domains. Well, a moment. They have a moment. Oh, yeah. I forgot the moment. It's called the orbital magnetic moment. And I get it. Maybe that's just when they realize, hey, we're all partying in the same way.

We're all spinning downward. Right. And we all like slacks. Yeah. We've got a magnetic field all of a sudden, small, but let's get a bunch of other ones and let's create a larger one. Right. And that moment is, it describes the force, I guess, the power and the direction of the

spin. Yeah. So yeah, when you have a bunch of them having the same moment, they kind of line up around one another when iron forms. That's right. And then that causes the domain, or that creates the little magnetic domains in the material. That's right. And if you notice that materials that make good magnets are the same materials that magnets

attract, then it's because they attract unpaired electrons that are spinning in that direction. It's the same thing. And you can also have something called diamagnetic, which are unpaired electrons creating a field that repels instead of attracts. And then some materials don't react at all with magnets. Like pine straw. I think now is the time for a word from our sponsor. All right.

Back to magnets because there's still some more to go. I mean, now everyone is listening. This understands magnets on an atomic level. Yeah. It's the spin of electrons. It's physics. Yeah. My favorite thing.

Yeah. It's actually appealed to me more than usual physics-wise. Same here. Remember the physics of surfing? I do. All right. So people measure magnets to see how strong the magnetic field is using something called a goss meter.

And flux or webers are the, what would you call that? Well, you measure flux in webers. Oh, okay. So flux is a line of magnetic force coming out of it. Oh, I botched that. That's all right. Okay. So the density of the flux is measured in either Tesla or goss.

With Tesla being 10,000 goss, which is pretty cool that you get a unit of measurement named after you. Oh, yeah. If you're Tesla. You better if you're Tesla. Sure. You get a lot of cool stuff. And you can also measure it in webers per square meter.

But really, who wants to do that? Yeah. Canada, probably. And then the magnitude of the field is measured in amperiors per meter or something called Orsted. Yeah. I like Orsted. Yeah.

I'm a fan of Orsted and I also like flux and Tesla's pretty awesome too. So where do we use magnets besides pizza reminders or doorbells or doorbells or of course speakers. We use them to, if you were in the cassette tapes back in the day, brother, you were in the magnets. Thank you. Yeah. We use them again in compasses, burglar alarms, electric motors. We use them to provide torque.

Yeah. Car speedometers. If you have an old fashioned cathode ray tube television set, you're using magnets. Yeah. Did you listen to cassettes? What? Sure, man. I grew up in the 80s.

Okay. I was just, I wasn't quite sure, you know, you're a little younger, but I didn't know. No, I was there. I was a late adopter. Oh, of cassettes? Well, no, of everything because what I would do is I would have a big collection and then be like, I got all these records. So I was late to cassettes and then I had all these cassettes.

I didn't want to switch to CDs until all my cassettes got stolen. Oh, yeah. And I was like, all right, I guess I'll get CDs now. Because I'm going CDs. Yeah. Yeah. No, I was there for the big transition from cassettes to CDs. Sure.

Remember, like they were across the board, $20, $19.99 for CDs. In the big box, too. Yeah. Remember? What a waste. See? Look at that. Maglev trains.

Yeah. We talked about this. We talked about one of our little one minute live action shorts online and maybe I'll post this when we release this. But the Maglev train system and a lot of roller coasters and things like that use super magnets. I don't remember that one. Yeah. The Maglev train uses it to propel the train forward.

Yeah. And roller coasters use magnets for breaking a lot of times. Oh, yeah. Like new ones. Yeah. The good ones. You don't remember that one? No.

We did like a dozen of them in four days. Okay. I don't remember that one. I'll send it to you. The, thank you. The magnetosphere is a part of our atmosphere. I guess it's outside of the atmosphere, but it surrounds Earth in a protective layer that protects it from charged ions known as solar winds.

Yeah. And when these solar winds come in contact with the magnetosphere, you get something that's called the northern or southern lights. Oh, okay. That's what that is. I knew we talked about that at some point. In another short. That's right.

Yeah. And for it, of course, the wonder machine would not be possible without magnets because it is magnetic resonance imaging. Right. You know? And just be resonance imaging without it. Yeah. There's no fun in that.

And then doctors sometimes use pulse electromagnetic fields to actually heal broken bones that haven't healed correctly. Yeah. Amazing. I looked into this. They have no idea how it works on a molecular level. Oh, really? What I know is that if you expose bone or tissue, I think bone more, more bone and muscle

maybe are easier to grow to an electromagnetic pulse, it grows. Even if it like it hasn't healed under after surgery or any other procedure, if you hit it with an electromagnetic pulse, it'll, you'll get a reaction and they're figuring out how to put this in garments for astronauts. Oh, really? Yeah. You suffer substantial bone loss on a very long microgravity flight. Yeah.

So they're figuring out how to weave it into their clothes so their clothes can get, can blast them with an electromagnetic pulse to make sure their bone density keeps up. Wow. Yeah. That's pretty cool. But they don't know why it works. They just know it works. Cows are pretty happy they're magnets because there's this horrific thing called traumatic.

You know, we'll just call it hardware disease. And this is when, when cows eat small metal objects that are in their food and it's pretty awful that that happens. But luckily they have a cow magnet to feed them and it, I guess, gathers up all this stuff and then they poop it out. They, I'll bet that's horrible to poop out. Isn't that what happens? Or it punctures, oh, the magnet?

Yeah. I mean, they poop it out, right? They put the magnet out. I don't know what it does. It surely doesn't just stay in the body, does it? I don't know. All right, I'm going to have to look into that some more. And people are known to put their arms into cows' rears.

Yeah. No, we, we, that some, some of them have a hole cut on their side, remember, so they can examine their stomach. Yeah. The one with the poor hole. Yeah. Yeah. That's pretty cool.

I'm going to try this one. Traumatic reticulo pericarditis. You practice that beforehand. Well done. So. There's nothing wrong with that. Yeah. Some people might be practicing hard words before you do a professionally released audio

program, a good thing. Um, if, uh, if a human swallows a magnet, that's not good. Yeah. You don't want to do that. Cows intestines and stomachs are different than humans intestines and stomachs. And if we swallow, especially more than one magnet, they will basically clamp your entrails together and you will be in big trouble and you'll have to undergo surgery to have them removed.

Yeah. So that's no good. Parents be cautioned to when your kids are playing with magnets, because kids like to swallow things. They shouldn't swallow. Um, since we talked about electromagnetic pulses being, um, capable of spurring bone loss, uh, is it spurring or spurring and spurring bone loss, spurring bone growth. Thank you.

Yeah. Um, you would think that people wearing like magnetic bracelets or magnetic insoles are getting some sort of benefit. There's no, there's no study that's ever shown that there, those things actually help. Although there's a lot of people out there who believe in static magnetic therapy, which is just a magnet on your skin. There's no pulse or anything right off. They think that possibly the people who are adherents to this, sure, think that it's either

attracting iron and the hemoglobin kind of makes sense to improve circulation. Or, um, it has some sort of effect on the cellular structure in the body, right? And that, that's why it helps your back in souls, help your back or a bracelet helps your arthritis. Yeah. Um, but again, there's no studies that suggest this. Well, it's big money. Um, Americans alone spend about 500 million per year on this kind of thing, um, and worldwide

about $5 billion a year on magnetic treatment. So the B. Yeah. That's a lot of dough. It is. Uh, and then, uh, those, one more thing, magnetized drinking water is a thing now to treat ailments. And I think that they have not shown in clinical trials that that's been proven either. Most of the minerals in drinking water are not ferromagnetic, so it wouldn't have anything

to do with it. And they, they found that, um, in clinical trials, a lot of the positive benefits, uh, come from placebo, maybe, or a passage of time, or maybe the fact that these, uh, insole cushionings are just better made and more padded to begin with. There's also apparently, um, a device that removes, um, hard water minerals from water using magnets, but apparently, again, it's not really doing anything as far as consumer reports says in a two year study. Yeah.

We had a water softener when I lived in Yuma. Yeah. And I'd never heard of that. And I was like, what? And it's like, you know, it's in the garage, just sort of looked like a hot water heater and it softened the water, whatever that means. Yeah. Do you know what it did?

It softened the water. Yeah. But I think I remember asking my sister what hard water did and she was like, oh, you could tell the difference. Like, I can't remember. It's skin real dry, I think. And I think, yeah. I don't remember.

Yeah. So that's hard water, everyone. If you want to learn more about that, type the word magnets into the search bar at house of works.com. It will bring up this, uh, awesome and exhaustive article. Also if you're interested in doorbells, type that word in the search bar too. And since I said search bar twice, it means we go straight to listener mail. Yeah.

I'm going to call this, uh, military shout out. We don't do shout outs that often. Sometimes we do. We get a lot of requests. We don't feel bad people if we don't. Yeah. Do your shout out. Um, this is from Trevor.

Hey guys, my name is Trevor. And yes, that is spelled with a B and not a V. And that is a long story that I'll tell you you'd like, but that's not why I'm writing in. I am currently serving in the US Armed Forces and I am stationed overseas. My wife and I recently welcomed my daughter into the world. Congratulations, Trevor. And wife. I'd like to spend some time with them, although not as much as I would like to, obviously,

before I had to come back overseas. It's been a really long, tough, uh, trip being away from them and even harder on our marriage. I work long hours and when I come home, uh, to talk to my wife, I really dread, uh, talking about work and she really hates talking about herself all the time. So that's when I bring up topics that you guys talk about on the show. I've listened for years and I have turned her onto them as well. And I just want to thank you guys and ask if you could give a shout out to her, uh, in Mr. Mail.

Her name is Tony and I. So Trevor and Tony, Trevor, thanks for your service, obviously. And both of you, thanks for hanging in there as a military couple. It's tough when you're away for that long and, uh, it's quite a sacrifice. My sister and her husband, he's a career Marine helicopter pilot, as I mentioned before. Yeah. He's been to Afghanistan, right? Yeah.

And they go for, you know, long tours, six and eight months at a time and you do enough of those in your life and you realize you're spending years away from your husband or wife totaled up and family and daughters and sons. And so it's tough stuff. So, uh, shouting out to you guys, hang in there. Yeah. Thanks, Trevor and Tony. Um, that's pretty awesome that we're like keeping their marriage happy.

Well, we're providing them sustenance to talk about. It's awesome. Exactly. Uh, if you want to let us know how we, uh, have helped your marriage, we're very interested in that. So try us on a shout out again. We don't do it very often, but it's worth a shot if you really think so. Sure.

Um, you can tweet to us at, uh, S Y S K podcast. You can join us on Facebook.com slash W should know. Send us an email to stuffpodcast at discovery.com and join us at our home on the web, www.stuffyoushouldknow.com. For more on this and thousands of other topics, visit how stuff works.com. This episode of stuff you should know is brought to you by jackthreads.com.