Daniel and Jorge Explain the UniverseFind out how microwaves work with Daniel and Jorge
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Hey or hey, I know you like the joke that any physics question I ask you could be answered with the Big Bang.
I think that's a pretty solid answer for any science question, you know, like why does this happen? And it's all because of the Big Bang?
Man, you are like a deep philosopher of science.
Sometimes I think I just heard you say the Big Bang too many times.
Well, I don't mean to burst your bubble, but I think I finally found a question where the Big Bang is not a valid answer.
What could not be due to the Big Bank?
Keep listening.
Hi am Horham, a cartoonists and the creator of PhD Comics.
Hi. I'm Daniel Whison. I'm a particle physicist, and I owe my existence to the Big Bang, as do we all, as does this podcast.
That's right, even this podcast so Welcome to Daniel and Jorge Explain the Universe, a production of iHeartRadio.
Welcome to our podcast, in which we explore things big and small.
It's right, things out there, big and small, out there in the universe, and even right here in our homes, in our everyday lives. Something that we use almost too much. I think, perhaps that's right.
One of the joys of being a physicist is looking around you all the time and wondering how does that thing work? And that extends to the cosmos and the stars and the big questions of the universe, but it also applies to just stuff happening around you. You know, why does that leaf dance that way? Why does the ball bounce this way? How do I make this thing happen? Or how does this thing am I kitchen do its thing? How does this magic happen?
There's crazy physics all around us, right, and potentially dangerous sources of radiation in our own homes.
That's right. Basically the whole universe is crazy physics. I mean, that's a good way to summarize the whole Right.
That's an alternate answer to the Big Bang? Why does this particle do that? It's just crazy physics.
It's better than the answer being crazy physicists.
Right, a physicist crazy because of crazy physics.
I'm not sure about the cause and effect there, Yeah, it might be the becoming a physicist makes you a little bit crazy because you see the world through different eyes. Right, everything you look at you try to understand in terms of an equation or model, or try to dig down and understand how this emergent phenomenon can be explained by tiny little particles bumping up against each other.
Yeah.
So on this podcast we usually tackle very big topics like the size of the universe or where did the Big Bang come from? But sometimes we like to tackle smaller topics or opistad are in everyone's everyday life. Yeah, so to the on the podcast, we'll be tackling something that everyone has in their kitchens. So today on the program, we'll be asking the question how does a microwave work? Or I guess more specifically, how does a microwave oven work?
Well, you know what a microwave is. You put the stuff in there, you press the button, It spins, it beeps, it turns around, and it comes out hot. Right, But how does that actually happen? What's the physics that's going on there?
Yeah? How do microwaves work? I mean, we've had them around for a long time. It seems right to heat up our foods our in our snacks in our hot pockets.
They first appeared in kitchens in the late fifties, I think, so it's been decades.
Faties around for a while.
Yeah, And like many useful inventions, they were discovered by accident. They were discovered by a physicist poking around trying to do one thing, discovered something else.
Useful another way to say time right, For a lot of people, it's sort of it's sort of a convenience appliance. Like if you were to heat things up in the regular oven, it would just it would take much longer, but in a microwave, things seem to get hot really fast.
Yeah. And you know, I don't want to take any esteem out of this this podcast episode, but I'll admit that the microwave in our kitchen at home has been broken for about five years. And yeah, it's built into the double oven thing we have, so to get it repaired, we have to replace the whole thing. So we just sort of put it off forever. And the truth is we haven't really missed it or never really noticed.
You've lived without a microwave for five years.
It is possible, people for that a microwave. Yes, it turns out you can make popcorn on the stove.
So what do you use it for? Which is like a storage you store some pots and dance it? Or did you clean it? Did you clean it before you abandoned it? I wonder if you opened this now.
It's never been cleaned. No, you know our pet rats like to hang out in there. No, okay, we don't use it for anything. It just you up space in the kitchen.
Wow, So you don't use the mark. So if you have to heat up a quick thing, you just what do you do? You eat it cold?
No? We got a toaster oven, We got an electric water kettle, We got a stove top that serves for mostly everything. Yeah, turns out life is possible without a microwave. But it's a fascinating object in so many people's kitchen, and lots of people swear by it. So I thought it'd be interesting to dig into the physics of it. And it turns out that very few people know how microwave works, and the people who think they know how microwave works probably have it wrong.
Yeah. I was reading through these notes and I realized I have no idea how a microwave oven works, or I thought I did, but it turns out.
That I don't, and so that sort of brings up an interesting question, like there's so many people out there who use a microwave, almost nobody knows how it works. How come nobody seems to have spent any time thinking about it or wondering about it. Is it just physicists who want to understand how the stuff around us work, and everybody else is sort of happy to just press a button and get their popcorn.
I wonder if it's a generational thing, you know, at this point, and most people grew up with the microwave. You know, it's sort of like it's just there. It's like nobody sits around wondering how a refrigerator works or how a pencil works.
You know.
I think my kids ask me how refrigerators work. I want to know how things work that existed in the universe before I came to be. I'm not like Big Bang, that's old news. I'm only interested in new stuff.
It's not trending the Big Bang, it's not trending. I don't care. So it's something that everyone is probably familiar with and maybe most people own. But we were wondering how many people out there and know how a microwave actually works.
That's right. So I walked around the streets of Aspen, Colorado, a place where people come from all over the world, with all sorts of different backgrounds, and I asked folks if they knew how a microwave worked.
So most people in Aspen, Colorado own multiple microwaves.
They probably own multiple microwave companies, That's what I mean. And they say, I don't care as long as the share price keeps going up.
Yeah, So think about it for a second. If you were skiing out there and Askma Colorado, and then a scruffy physicist asks you, hey, how does a microwave work? What do you think you would answer? Here's what people had to say.
Nope, best guess microwaves of.
An electricity fastened through food.
No electricity turned into.
Something genetically modifies your food.
Yeah, it has a right.
Onto, right on too. And how does that heat up your food?
The moisture in the.
Food is what caused the heat up.
Yes, electricity, then, so.
Can you english something abound electricity coming down in waves? You'd say, start and then what happens microwaves?
No, I do not know.
Do you know how a microwave works.
I do, oh how it works? Maybe not?
We press pluster just second spots and then start.
All right. It seems that those microwave company owners in Asthmen don't really have much of an idea of how they work.
Well, I was amazed at the huge variety of answers. I mean, we got radiation, we got genetic modification to the foods. There's that one guy who seemed to understand how microwave worked, but he could only explain it in Japanese to his wife.
Well, that's the same with me. I know how it works, but I only know how it works in Japan. I like the guy who said, how does a micro work? You just press the start button. That's how it works, right.
I know, Like I was asking for tips, like help, I need to use the microwave and I don't know how it works.
Please give me advice, tell me my food is cold, like.
I'm out here on the street with my recorder looking for tech support from my micro.
Well he would have been helpful.
Yeah, yeah, And you know, and you were heard a couple of people say or what I think is a common trope, which is that the microwave heats up the water, right, which I think is a common misunderstanding. We'll get into it later, but that's not how a microwave works.
Right, Yeah, that's what I thought too. And also some people said it has to do with electricity, like somehow it uses electricity to zap your food.
Yeah, and you know it does use electricity. It's not like it's a coal powered microwave or something.
Steampunk steam punk microwave, like you have all the steam, but you convert it to microwaves.
Yeah, somebody out there probably has done that, you know. On our recent episode about gravitons, I wondered out loud what a gravitron was, and that moment in our podcast I think might have generated the most listener response because I got dozens of emails from people who had ridden in their childhood a gravitron, an amusement park ride. So that generated the most the most emails of any thing we've ever done so far.
I actually know that because that was on the latest season of Stranger Things.
Yes, you're right, there was a scene in the gravitron. So if anybody out there knows of a coal powered microwave, please ride in and send us a picture. I'd love to see it.
Well, so, not a lot of people know how a microwave works, and I didn't know apparently how a microwave works. So let's get into it. But maybe first weh you talk about how normal ovens work, like the ones with gas or the ones that are electric, not the microwave kind.
So a normal oven basically works by heating the air inside the oven, and then the air heats your food, right, And that's you'll notice this because if you open a normal oven, you get like a rush of hot air that comes out and burns your face, right, Whereas if you open a microwave, you don't notice that.
In a regular oven, you rely you like, you put the energy into the air, and then you rely on the air to give the energy to your food.
That's right. And remember, on a microscopic level, what's happening is that the air is heating up, and that means that the air molecules are getting faster. Right. We talked about temperature in another episode. It's sort of a crazy concept, but the simplest idea is that you're just speeding up the air molecules, so they're zooming around faster and faster inside the oven, and sometimes they bounce into your food and they deposit some energy, so they heat up the molecules in your food. Right. Maybe your oven is gas and has little flames, or it has heating element if it's an electric oven, and that heats up the air, right, which speeds up those molecules, and they bounce into the molecules of your food and heat them up.
Yeah, when you put it like that, it seems really inefficient to think about ovens like that. The air and then the air you have to wait for the air to bump into your food, and then it only bumps into the surface, right, the outer skin of your food. So that's why it takes a while to heat up in a regular oven.
That's right. And they're super inefficient in my house because every time I'm baking something, somebody will walk by the oven every five minutes and open it up. Ooh, what's in there? And then all the hot rushes out and you gotta heat of the whole oven. Again.
I'm surprised you're regular oven works, Daniel.
I'm gonna put a lock on it or something.
But yeah, that's a campfire every night.
That's exactly why. That's exactly why the food in your oven heats from the outside in because the outside is the only part exposed to the air, right, So the outside of your food, the outside layer gets heated by the air and the inside gets heated by the outside. Like you're cooking a turkey, the skin gets hot first, and then the heat of the skin cooks the next layer, and that layer cooks the next layer, and that layer cooks the next layer. So it's sort of like heat propagating through the turkey, but has to start from the outside. That's the hottest part.
Right, And that's kind of then that's kind of good sometimes because that's where you get you know, crunchy crusts.
Yeah, exactly, you get this browning effect from the hot air. And that's because the air can get to a sort of a high enough temperature to be like caramelization, and that gives you the good browning stuff. And you know, sometimes you want that. You want the outside to be crunchier and hotter than the inside. Like for a turkey, you don't want the breast meat to get up to a certain temperature because then it gets dry, but you do want the outside of a higher temperature. So for things where you want the outside hot or and the inside a little bit cooler. A convection oven is perfect.
Okay, So it doesn't sound super efficient.
But it's an old, old timey trusted technology we've been doing. We've been using ovens for thousands and thousands of years.
It doesn't break down like it doesn't crib.
That's right. I mean in the old days, before we had gas ovens and electric ovens, an oven was just like an enclosed space with a bunch of burning wood in it, right, And people still do that, like a pizza oven.
Right.
It can get up to eight hundred degrees or nine hundred degrees, and you see these things, they're just like they got wood burning in the back. And it's just an enclosed space to trap the heat. Because if you have a fire without walls around it, then the heat just rises and you can cook over it, but it's much less efficient. So you just enclose it to sort of capture the heat where you are. And that's an oven. That's all an oven is is a heat source and something to capture it to the air stays hot, all right.
That's how normal ovens work. So let's get into microwaves. But first let's take a quick break.
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All right, we're talking about microwave ovens and how they work. So Daniel break it down for us. How does a microwave oven work?
Well, maybe we first we should figure out we should talk about what a microwave is, right, Like, what is this thing?
We tackle the word oven. Now we're tackling the word microve waves. But first let's bring it that into micro and wave.
What is the letter M really means? What is letter I really mean?
Three hours later we'll get to the answer.
It's pretty simple. Actually, a microwave is just a kind of light. Right. Remember that all these things gamma rays, X rays, UV light, visible light, radio waves, These are all just parts of the electromagnetic spectrum.
It's not like a special kind of ray or a special kind of particle, or you know, laser is just plane o light.
It's just plane old electromagnetic radiation, right, And a microwave just refers to the wavelength of that radiation. So remember, the thing that differentiates a gamma ray from ultraviolet light, from visible light from X rays or radio waves is just the frequency of the wiggling right. All these things are electromagnetic fields oscillating up and down and left and right, and the speed at which they oscillate, how many times they oscillate per second, right, or equivalently, the wavelength of their oscillation right, how long that wave is determines which one it is, And so radio waves are the ones with the really long wavelengths. Like there are radio waves that have lengths like, you know, dozens and dozens of meters, microwaves. It's sort of a confusing name because microwaves are radio waves with shorter wavelengths, so down to about twelve centimeter, But it's only shorter compared to radio waves, which have like dozens of meters of wavelength. They're not short compared to light, visible light like nanometers.
They're not microscopic, that's.
Right, They're only micro compared to really big radio waves scale thing. Huh.
So there, microwaves are actually like megawaves compared to like the visible light that we all see every.
Day, Yeah, which is wavelengths of like hundreds of nanometers, which is tiny. Right. These things have wavelengths that are you know, twelve centimeters. That's you know, the size of your hand or something like that. So these things have real physical wavelength.
Wait, are you telling me that physicists names something in a confusing way?
What are you telling me that you're surprised that confusing?
To sha touche i should.
Anything named in the pre Jorge epoch is defined to be confusing because you were not involved.
Yeah, yeah, the PJ.
We don't like to talk about it. You know, it's a dark period in the history of physics, but it does exist.
Okay, So there there are microwaves, but they're not really micro they're actually like, you know, twelve centimeters. It's sort of like the length of your hand.
Yeah, yeah, exactly, And so that's what a microwave is. And then you might wonder like, all right, but you know, how does that heat my food? If I shine my flashlight at a turkey, it doesn't cook it, right, cook it not?
Well, it depends on your flashlight, doesn't it.
If your flashlight is the large Hadron collider, then yeah.
Maybe, yeah, that's what I mean. It's not that the regular light doesn't cook, it's just that it doesn't cook as well.
Yeah, that's true. It does deposit some energy, it just doesn't have that much energy on it. But essentially, the way a microwave oven works is that it blasts your food with microwave radiation, right.
Which, again, radiation, It sounds scary, but it's really just light.
Yeah. Light is an example of radiation. So this is just another kind of electromagnetic radiation. And you might be wondering like, well, okay, why does this specific frequency of radiation tend to heat up your food? Why does that do that? Right? Well, one thing you'll notice is that when you open up a microwave oven after you've cooked your food, right, that the air inside the microwave oven is not hot. So a lot of people think that the way a microwave works is that the microwave radiation heats up the water inside the food.
Yeah, I've heard I've heard of that. Yeah, Like somehow there's something like it only heats up the water molecules, or preferentially the water molecules in your food. That's kind of why, Like if you stick a plastic plate, it's not gonna heat up as much as if you put, you know, a hot dog.
And there is some truth to that, right, a microwave will heat up some kinds of food more than other kinds of food. But the reason that some people give is that they think that a microwave has like a resonant frequency with the water. Remember, microscopically, water is made out of molecules, and those molecules can do things like spin and vibrate, and like all atomic stuff, it's quantum mechanical, which means it can only accept radiation. It's certain frequencies, Like we talked about how atoms can absorb wavelengths, certain wavelengths of light and not other wavelengths of light. So some people, I think, imagine that this is what's happening inside your microwave, that water can absorb frequency at this wavelength and the air and the other stuff can't. Right, So that's a common misconception right.
And when you say resonant frequency, you mean like kind of like a water. It's the idea that water has kind of an internal bounciness to it, right, like an internal like frequency. It likes to bounce around like a guitar string.
Yes, exactly, And it's true of every atom, right. They do have special frequencies at which they like to vibrate, and it depends on the atom and how it's built and how the electrons are organized and all that stuff, and so they do have special resonant frequencies that they do like to absorb radiation. But that's not what's happening here. That's not the way that the microwave works. It's not it's not definitely not No, it's a totally different but really fascinating mechanism.
You just nuke my brain here. I just tried my start my illusion of understanding here. Okay, So it's not making a resonance with the water, So how is it? But it is it is sort of related to water, right, Like, there's something about water molecules that microwaves are kind of specially tuned to a heat up.
Yeah, and it's a different process. It's called dielectric heating. Essentially, it's because water molecules they have the same number of positive and negative charges, but they're not exactly balanced in the same place, right, which means that one part of the water molecule is a little more positive and another part is a little more negative. So overall there's a little bit of a separation of the charges.
So what happens when electromtid water is more optimistic dealing, what's more pessimistic?
That's right, you got the upside in the downside somewhat.
Some water molecules are like this, glasses half full of us is like this, classes have empty of us.
It's a big But what happens when electromagnetic waves come by? I remember electromagnetic waves interact with things that have charge, right, negative and positive charge, and so what they do is that one part of the molecule gets pushed one way and the other part has the other charge gets pushed the other way.
You're saying, like a water molecule is kind of like a little where one end is sort of negative and the other side is positive. So it's not like perfectly even.
Yeah, it's kind of like a magnet in that there are north and south right but in this case, we're talking about electric charges, and they're positive and negative, and the waves come by and they tweak it, and they tweak it differently because the charge is different on one side than the other. Right, it's overall neutral, but you've separated the charges a little bit so that you have a positive and negative. So the wave gives the two sides a different kick right in different directions, and that spins it. But the thing about a wave is that it's a wave, which means it goes up and then it goes down. So now the other part of the wave comes by and it spins it the other direction. And so essentially what happens when these waves come by a water molecule is they spin them back and then forth, and then back and then forth, and so they're sort of like they're spinning all the little molecules. All the little water molecules in your food gets spun back and forth by this microwave.
So it's not like an internal vibration. It's more like a but it is sort of a essonance right like in how it spins, like it likes to spin at that frequency or the special resonance.
It's just it's the fact that it has this Anything in your food that has a electric dipole will get spun this way. It just so happens that water is pretty good at getting spun that way because the arrangement of the atoms inside the water molecule gives it a larger electric dipole than things like.
Plastic which we're not supposed to eat.
Which were not supposed to eat. And so what happens. You heat up all the water molecules and they got a lot of energy now, right, and then they spread the energy did the stuff around it. So you're cooking a turkey, right, you heat up with the water molecules, and then the heat spreads out right from the water molecules to the other stuff that didn't get sort of mixed up or spun around. I'm sort of thinking about it, like to cook something with a microwave. You take like a billion tiny little spoons and you stir up each of the little water molecules.
You're like shaking. You're shaking each molecule.
Yeah, exactly, you're shaking their booties and they're dancing and they spread their energy out to other stuff. And so that's how the non the stuff that in your food that doesn't have an electric dipole also gets heated up.
So it is sort of there is something about water, but it's not. It doesn't have to do with this sort of internal resonance. It's just really it's just it just has this kind of a magnet like structure.
Yeah, exactly, it's the electric dipole structure. And the fascinating thing is that for this to work, the water molecules have to be able to wiggle, right. The key is you're like turning it and then turning it back, and turning it and turning it back. So this is something I didn't understand very well, but that frozen water is harder to heat up in the microwave than liquid water because the molecules can't wiggle as much because they're trapped in this ice crystal.
It's frozen too, right, So it's just naturally harder to heat up because it's already cold.
That's true. It takes longer to heat up to a certain temperature, but it absorbs microwaves less efficiently when it's frozen than when it's liquid.
So it like it takes in the energy, but because they can't move, that energy doesn't get absorbed.
Yeah, exactly. They the wave comes by and it tries to wiggle that little water molecule because it has that electric dipole, but it just doesn't get wiggled as much, and so it doesn't absorb as much energy. And then you know, later when it's freer because it's you melted it a little bit, then it can get mixed up even better.
Wow.
I imagine, you know, imagine trying to take a frozen block of water and mixing it up until it melts. Right, that's not going to be very efficient. But you could put a spoon into a bowl of water and mix it around until it got really hot. That's more efficient.
And I guess it's convenient because most of the things we eat have water in it, right.
That's right, And that's a convenient overlap between our diet and the physics. Another misconception that people have is I think that people think that microwaves cook their food from the inside out, or that it cooks it totally evenly, right, that it doesn't really matter where it is because it's this mysterios quantum mechanical thing that's happening.
So you're saying it doesn't heat up from the inside.
No, it doesn't actually, because these microwaves penetrate the food, but they only penetrate a few centimeters. They can't get all the way in. Their energy gets absorbed before they get really deep into the food, and so the stuff that's cooking the inside of your turkey in a microwave is still the outside of the turkey. Right. All you can do is heat the outside and then the inside gets heated by the next layer. And a lot of people have microwaves with like a defrost setting on it and you press the button. It doesn't automatically. What it actually does often is that it runs for a little while and then it just turns off. It looks like it's doing something, but it turns off the microwaves and it just sort of lets the heat flow around for a little bit.
Oh, I see, So it doesn't cook. The outside doesn't cook, it's just you know, heats it up in bursts.
Yeah, exactly. And different parts of your food will get hot differently, and the reason is, of course, you know, different parts of different amounts of water. But also it's really difficult to get an even dose of radiation, right. It's generating this radiation using a little cavity called a magnet and it's really hard to get like an exactly even density of microwave radiation inside your microwave, and so you have hot spots and cold spots.
Yeah. Well, I always thought that the reason that the inside get hotter than the outsides was because you know, I imagine my food is getting bombarded by microwaves from all directions, and it's the center of my food that's getting hit by all directions more than any other part, you know what I mean, Like it's surrounded, so all the microwaves sort of concentrate in the middle. Isn't that the reason why maybe the center would heat up more.
Well, that would be true if the microwaves are sort of aimed at the center from some source on the outside, But that's not how they're generated. This one source, this magnetron, which is a pretty cool name. It generates all the radiation and this little wave guid that just sort of dumps it out into your microwave. And more expensive, fancier ones have more complicated or double magnetrons to try to make it even. But the best thing you can do to get even cooking of your food is to put it to make it spin, so it sort of rotates your food through the hot spots and the cold spots. But you shouldn't just put it in the center.
Right.
If you just put it right in the center of your turntable, then all your food is doing is spinning around. It's not actually moving through the hot and the cold spots.
All right, let's get into how microwaves actually make the microwaves, But first let's take a quick break.
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All right, Daniel. So let's get into how a microwave makes microwaves. And you're saying that it uses a couple of transformer toys.
This alien came to Earth and transformed from a killer robot into a kitchen appliance.
And its name was Magnetron.
Was magnetron no, And this is why microwaves were discovered by physicists. There's a guy, Percy Spencer, and he was playing with magnetrons because he was interested in using microwaves for like navigation and for radar. I think he was probably funded by like the US Navy or the Air Force or something for.
Like communications, like to transmit stuff.
Yeah, to either transmit stuff or just detect, like you know, where are the rocks and where's the coastline? And in this kind of stuff, you know, useful radar stuff where are the enemy ships and all that stuff. And he had built this magnetron and a magnetron is just something that generates microwave radiation.
How does a magnetron make microwaves?
How do you make microwaves in general? Well, the way to make radiation is, you know, you find something in nature which normally produces that radiation. You know, because it has a resonant frequency, it likes to wiggle in exactly the right way to make that radiation. You can do that, or you can build a cavity that makes it so that electrons have exactly that resonant frequency, Like you build a little metal box and so that when electrons go in there, they like to shake around at exactly the frequency you want to generate. And that's essentially what a magnetron is. Yeah, exactly. It's a lot like a musical instrument, you know, and a musical instrument, the shape and the size of the cavity determines exactly the acoustic waves that you can generate from it. Right, you can shorten the cavity link in the cavity by putting your fingers on the keys exactly. So magnetron is just a cavity where you shoot electrons. You have magnetic and you have magnetic fields in there in order to generate exactly the right kind of frequency. And you can generate different frequencies by having a different sized cavity.
So you shoot the electrons in and they all sort of sync up and then outcomes this kind of synchronize ray of light.
Right, yeah, of radiation. And for those of you who know any quantum mechanics, you know that when you create a confined space like an infinite well, for those of you have taken physics, that's when you get quantum mechanical effects. That you get special resonant frequencies energy levels for example. So the same way you have energy levels around an atom, you can have energy levels inside a cavity. And so you get electrons in there and they like to wiggle this energy level and then they jump down an energy level and give off that radiation, which is then at the frequency that you want.
So the microwave in my kitchen has one of these magnetrons like a little two.
Yeah, exact fact. Everybody who has a microwave has a little radiation creating device in their microwave. But don't worry, right, that sounds crazy, like what I'm exposing myself to radiation? You know, you're exposing your coffee to radiation. But also the microwave has metal box around it. And the cool thing about electromagnetic radiation is that it's basically blocked by almost any conductor. So you have a wall of metal or even just like a grate of metal something we call a Faraday cage, it will cancel out almost any radiation. So the microwave radiation inside your microwave is basically trapped there by the metal that goes all the way around the box.
Because I think I always assume that my microwave has like several microwave guns amy at the middle, but you're saying there's only one tube here, like general spewing out these light waves.
Man, you made a funny mental image there with microwave gun imagin shooting these things at each other. Not a good idea. Most of them have a single one. Yes, some of them have double ones, or you know, more expensive laborate ones might have multiple magnetrons, but you only really need one and it then you just need to guide the radiation using you know, any sort of metal tube. The radiation will propagate down that tube into your cooking area.
That's pretty cool. So then how did they how did he discover the microwave.
He built this magnetron to try to generate microwaves, you know, for these other physics studies. And I guess he was hungry. He was a guy that like a snack, and he had a chocolate bar in his pocket, and he noticed that he turned the thing on. Literally, the chocolate bar would melt and.
Like a couple of centimeters from his private parts.
Exactly exactly. I'm thinking, Okay, you're cooking the chocolate bar. You're also cooking the physicist, you know, his chocolate covered physicist here is but we're preparing. But yeah, that's what he noticed it, and he reported it to his employer. He's like, hey, look turns out, you know, my whole radar project didn't work, but I invented a new kind of oven for you.
We can't spy in the Russians, but hey, we can all have warmer meals.
I always wonder how executives feel that way. You know, they give you money because they're looking for a certain contract, and you come back with like teflon or microwaves. Right, all these things are discovered by accident in research environments, it's called the pivot. Yeah, the pivot, and I wonder what like amazing inventions were thrown away by small minded executives are like, that's not what we asked you to develop. Put it on the shelf and go back and work on that ray gun.
Make the ray gun work.
And for those of you who are scared of radiation, whatever, don't worry. These things are really safe. They surround your microwave with plenty of metals. There really is no leakage, and it's really it's even pretty safe to like put your face up against the microwave. They used to test microwaves really carefully to make sure that none of this radiation leaked out to like, you know, cook your brain. But for so many years they were so safe they couldn't measure anything that these days they don't even bother anymore.
And it's really you're just hitting it with the light, you know. It's not like you're hitting it with particles that then make the food radioactive. Right, that's not what's happening.
Oh no, no, no, It certainly does not make your coffee radioactive. Although that does sound like an awesome superhero creation story.
Microwave man he.
Drank radioactive coffee and gained that coffee's proportional strength.
Just heats up the food, right, It doesn't make it, It doesn't give it the ability to emit radiation.
No, just heats of the food. But you know, if you were inside a microwave, it would heat up you also, right, you would literally get cooked. So they are dangerous, but only inside the microwave. Outside is not dangerous at all.
Cool, So that's how microwaves work. I feel like I've been irradiated with knowledge today.
That's right. A small amount of knowledge leads to a lot of inside. So the next time you're turning on your microwave, remember you're blasting it with radiation. That's basically just taking a little spoon to all the molecules in there that have a little dielectric field and spinning them around to heat up everything else. So there is physics that's making your food taste it.
And as a public risk, just remember contents might be hotter than expected.
That's right. And you know, some people like microwaves, some people don't like microwaves. You know. One of the limitations is that you know, did get that crispy browniness, but you can just you know, put it in your toaster. Upon afterwards if you really want that crunchiness.
Yeah, that's that's my strategy. Heat up the insides and then you toast the outside. On our next podcast, how do toasters work?
How to eat dinner at Jorge House.
How to fix Daniel's microwave level?
Yeah, please, I'd love to hear that. Podcasts for less than ten thousand dollars.
All right, everyone, We hope you enjoyed that. See you next time.
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