When I worked in a condensed matter physics lab, I touched a quartz tube recently heated by an oxy-hydrogen torch. Burned my thumb! Fortunately, it was only superficial.
I did this on accident also, my skin turned white. Luckily it was only a tiny spot and after the blister and new skin you can nearly notice it anymore. The funny thing about the experience for me is I didn't feel it at the second it happened, and the pain just got gradually worse after I realized. It probably got to peak pain about 10 minutes after. The body is strange the way it works. Pretty amazing really.
I was touching red hot pen springs for fun. Quite an experience! No pain, only parallel lines burnt into my fingers, pretty interesting way to modify fingerprints.
I touched a hot plate which was turned on, because i thought it was off. I got near it first to test if its on, didnt feel the heat somehow (maybe it was going on and off and at that moment it was off), and to be sure that its off i touched it. Instantly retracted my hand. This left a white powder on the surface of my hand. Luckily only the very top layer got burned to dust, and the below layers where fine.
Sixty Symbols did a video on this topic 11 years ago called "Negative Temperatures are HOT" referring to negative absolute temperatures rather than negative Fahrenheit or Celsius. You can also think of them as beyond infinite temperature. Heat will _always_ move from a negative temperature region into a positive temperature region no matter how hot the positive temperature is. You can literally heat the Sun a minuscule amount by shining a laser at it.
The laser light is transferring energy. Whatever the laser is shining on is accumulating that energy so it is a question of time and energy not simply energy.
This is a great video, I design laser engraving systems. We go down to spots with a size of a few microns to get some enormous power density. This is a great basic video explaining some of the phenomenon
I learned yesterday that we figured out what was diamonds were by vaporizing them, and then doing experiments to see what the gas was! This was in the 1700s! One of the methods they used was simply lenses. How crazy is that. I've seen people burn rocks, but diamonds just using the sun is crazy to me. He should do this himself. Makes me appreciate glass. Where would science be without it. They used glass lenses to vaporize diamond to capture the gas in glass vessels to weigh the gas! Then used glass beakers to do the tests.
Two different proceses: first the IR cameria is simply making an inference between light emission & temperature & its based up on limited IR spectrum, not the full light spectrum. Visible light has a correspondence with much higher temperatures than IR, but the thermal camera does not interprete white light with heat. When you shine a high watt light source on a object that absorbs the light, the light stimulates the electrons in the object causing increase molecular viberations (ie heat).
I've been a manufacturing laser operator for 14 years and i can attest that the latest fiber lasers are indeed insane. at a mere 6kw you can easily cut through 1 inch steel plate.
Thanks! I needed this video to explain how that little laser of only a couple of milliwatts somehow managed to heat the parts of the radiometer all the way to incandescence! 🔥
well as it is emitting energy, and that energy is usually measured over an area not a point, so you can concentrate that energy by reducing the area that it is dissipating energy over. so yes you can focus a collimated beam of light and make it higher powered.
Fun fact: Because of the definition of temperature (which only makes sense in macroscopic systems, as it deals with the entropy concept) T=dQ/dS, in systems where there is a maximum energy there are states where temperature is negative. Additionally these negative temperature bodies always transfer heat to positive temperature bodies. A good example of a negative temperature system is a laser 🤯🤯🤯
What happens if you get like a spherical array of those laser cutters or even stronger lasers, pointed them all inwards towards the direct centre of the sphere and then fire them at something in that centre point?
It'll likely vaporize quite rapidly. It's basically a lower power version of one of the proposed methods of igniting fusion. Fuel is inserted into a pellet and it gets hit with high power lasers from multiple directions; the blast wave of the shell vaporizing compresses the fuel to fusion conditions.
Did you say that you cannot focus sunlight to a pinpoint that is hotter than the source? If I have a very large surface at 1000 C, and I focus the light (IR) to a pinpoint, the pinpoint will not be hotter than 1000 C?
@@DANGJOS You don't help anyone by just repeating the statement. The Stefan-Boltzmann Law works with an area, the magnification(in one direction) has an effect for the equilibrium of the heat transfer.
So if I understand it correctly. The laser just turns the light energy into heat energy at the point of impact. The total energy of the light energy will be more than the energy required to heat up the material by X amount. other will be lost in form of reflected light or other forms of energy. You literally said it. light has no temperature. so no paradox?
That water flosser looks cool, but it's really bulky. What if we could attach it to the faucet? I bet you wouldn't even need to put a motor in it to get it up to pressure!
youre actually mixing up some stuff here, the magnetron of an microwave is not around 100 degrees. or rather the electrons in it are extremely hot by being pumped by electromagnetic fields, about 80 000 K (although measuring this in temperature is kinda pointless), above this a magnetron should not heat up anything. not normally a concern obviously but quite different from the negative temperatures that lasers have.
7:34 doesn't that mean you can heat an object more assuming you focus all of it on a smaller object since a smaller object won't radiate the heat as fast right?
What confuses me is the sun is continually adding energy - it's an ongoing nuclear reaction continuously pumping more energy out in the EM spectrum - it's not coherent light like a laser, but there's not only the blackbody light radiation coming from the sun, but all of the photons generated by nuclear fusion as well - so it should theoretically be able to do what a laser pointer does a trillion times over.
question , If a laser runs for say 1 hour just pointed at nothing , say out to space , and you measure the lasers head body cavity temperature , Then under the same conditions , but , this time the laser is being used to say , cut metal , Would we measure the lasers body , or head, or cavity etc.. to be hotter ? In other words does a laser get hotter if its doing work ? has a load on it , compared to no load . Thank you very much.
Once the light is emitted from the laser, it does not interact with it anymore, whether it ends up hitting metal or nothing, the laser has no "idea" what happened to it because the information does not come back. One exception would be if some light is reflected off the metal and comes back to hit the laser, heating it up, but considering your question I think this is a technicality
Laser dust, aka metal dust. The exhaust is drawn into an air handler. If you want mars soil, ask for some laser dust. It's nearly the same density of air. Gets everywhere. Probably giving me Parkinson's in a few years.
To be pedantic; single particles or atoms do not have a temperature. Temperature is an emergent phenomenon categorized by the aggregate motion of the particles in the system.
I think the rough answer is that the kinetic energy of the particles goes up faster than the speed. This is because the relativistic mass of the particles goes up with their speed. To reach the speed of light the particles would need to be infinitely heavy - which never happens. In a sense the energy creates extra mass. E = mc^2 comes in here somewhere, I think my explanation is basically correct, but probably no use the latest way of explaining it.
Is it possible to have an objects temperature so hot its black body radiation is averaged well beyond the visible light spectrum rendering it 'invisible' (well black)
So If I use a match 600'C to light a piece of wood in the forest, generating a huge fire reaching 2000C' You'll see that with a single source of lower energy I generated MORE energy 😂😂😂😂😂
Thermography cameras have sensors registering radiation in the range 7000-14000 nm. There is no reason at all why an infrared laser at 989 nm should register on such a camera. It is just like wondering why you can't see blue with a red filter before your eyes.
It's really disheartening to see the false analogy you used of sunlight thru a magnifying glass & laser light. Light is just a method of energy transfer so the proper analogy would be the power input (battery chemistry/electrical potential) of the laser vs the Sun's surface energy (the atomic/subatomic reactions that power it) to the magnified beam. Therefore it would be more correct to say the heat generated by a laser can be no more than the total power of the energy source powering it. If one put a short across the lithium battery source (or the building's electrical lines) they would reach an equivalent temperature rating.
He is talking about limitations on temperature produced, not about limitations on total energy or power. Temperature changes have some relation to energy and power, but they are not the same thing. I don't think he was using an analogy, but a comparison.
The video feels incomplete, light goes in and the light-matter interaction is where all the black box magic lies, but this video didn't explain that. Would that same laser melt me up like it did the metal? Why or why not? How does the energy of the laser get converted into thermal energy? The material absorbs it, and how much it's absorbed is material-dependent, why? What's the difference between a continuous wave laser and a pulsed laser?
Hmm ... that's against my intuition 🤨 imagine we use a lens with an area of, lets say, 10 square meter, and focus all the light on a grain of sand (which is insulated within a thermos can by the way), then the grain gets so much more energy compared to its size Would it still not get hotter than the sun? Where does the focused energy go then?
They aren't. Microwave ovens are usually in the range of about 1000 watts. Modern household LED lightbulbs are on the order of 10 or 20 watts. Light fixtures also tend to disperse the light rather than focus or contain it within a small space. Even if you used a 1000-watt LED light fixture and focused all of its light on a single object, it won't heat up as quickly unless it's black because it'll be reflecting a considerable portion of the light. Microwaves and infrared tend to be readily absorbed by most substances, particularly water and oil (major components of most food). High energy light tends to penetrate objects rather than be absorbed, this is how x-rays can be used to image bones, most of the light passes right through flesh without being absorbed.
Of course focusnig sunlight can heat up material hotter than the surface of the sun... imagine focusing the suns entire radiation output onto a penny... you reall expect it to only heat up to a few thousand degrees?
If the probability of anything else is basicly zero you are basicly guaranteed it will happen. Gamblers are guaranteed to lose money in the long run, its not just suggested by statistics. And if you won money, you just didn't play long enough.
"Imagine if we shine ten million of them in the same spot". For some reason I was expecting an xkcd collab after that.
Lmao me too
YH. That would be something
"Imagine if we shine ten million of them in the same spot" National Ignotion facility has entered the chat.
I Accidentally put my hand on some 800C Steel while using an oxyacetylene torch one. Sizzled like your 'assistant'
Been there. My fingers have additional contours
When I worked in a condensed matter physics lab, I touched a quartz tube recently heated by an oxy-hydrogen torch. Burned my thumb! Fortunately, it was only superficial.
I did this on accident also, my skin turned white. Luckily it was only a tiny spot and after the blister and new skin you can nearly notice it anymore. The funny thing about the experience for me is I didn't feel it at the second it happened, and the pain just got gradually worse after I realized. It probably got to peak pain about 10 minutes after. The body is strange the way it works. Pretty amazing really.
I was touching red hot pen springs for fun. Quite an experience! No pain, only parallel lines burnt into my fingers, pretty interesting way to modify fingerprints.
I touched a hot plate which was turned on, because i thought it was off.
I got near it first to test if its on, didnt feel the heat somehow (maybe it was going on and off and at that moment it was off), and to be sure that its off i touched it. Instantly retracted my hand.
This left a white powder on the surface of my hand. Luckily only the very top layer got burned to dust, and the below layers where fine.
Sixty Symbols did a video on this topic 11 years ago called "Negative Temperatures are HOT" referring to negative absolute temperatures rather than negative Fahrenheit or Celsius. You can also think of them as beyond infinite temperature. Heat will _always_ move from a negative temperature region into a positive temperature region no matter how hot the positive temperature is. You can literally heat the Sun a minuscule amount by shining a laser at it.
Yes! The Action Lab also has a video on this
@@DANGJOSwhich video?
@@blueslime5855 If you search "what happens if you focus a laser Action Lab" you should find it
I'm outside using a standard laser pointer but I'm trying my best to help make winter just a little more mild this time. You're welcome guys!
The laser light is transferring energy. Whatever the laser is shining on is accumulating that energy so it is a question of time and energy not simply energy.
This is a great video, I design laser engraving systems. We go down to spots with a size of a few microns to get some enormous power density. This is a great basic video explaining some of the phenomenon
comically small sun
I learned yesterday that we figured out what was diamonds were by vaporizing them, and then doing experiments to see what the gas was! This was in the 1700s!
One of the methods they used was simply lenses. How crazy is that. I've seen people burn rocks, but diamonds just using the sun is crazy to me.
He should do this himself.
Makes me appreciate glass. Where would science be without it. They used glass lenses to vaporize diamond to capture the gas in glass vessels to weigh the gas! Then used glass beakers to do the tests.
2:39 crazy vending machine they got there.
LASER = Light Amplification by Stimulated Emission of Radiation 🙂
Radiation really is 🤩 .
yes this sums up the whole video actually
@@BibhatsuKuiri thats what im trying to say.
GIF.
Stimulated 😍😍
Dude, what were you eating!? 4:52
Still getting my head round this one!
1:00 "well light doesn't have a temperature" that's the end of the video.
exactly
Two different proceses: first the IR cameria is simply making an inference between light emission & temperature & its based up on limited IR spectrum, not the full light spectrum. Visible light has a correspondence with much higher temperatures than IR, but the thermal camera does not interprete white light with heat.
When you shine a high watt light source on a object that absorbs the light, the light stimulates the electrons in the object causing increase molecular viberations (ie heat).
Note to self: Never be an assistant at ActionLab! 🤣
😅😂 But you can send him cool stuff to experiment with. I did.
@@westonding8953 Your hand?! 😉
I've been a manufacturing laser operator for 14 years and i can attest that the latest fiber lasers are indeed insane. at a mere 6kw you can easily cut through 1 inch steel plate.
Should have gone to the styro Pyro that guy can build a laser
Thank u for creating vids like these
Your channel is one of the few that really enjoys the quality of content. Keep it up!😆🎽🙉
Thanks! I needed this video to explain how that little laser of only a couple of milliwatts somehow managed to heat the parts of the radiometer all the way to incandescence! 🔥
You are a world class geeker and I am here for it.
As always, Great video.
well as it is emitting energy, and that energy is usually measured over an area not a point, so you can concentrate that energy by reducing the area that it is dissipating energy over.
so yes you can focus a collimated beam of light and make it higher powered.
Remember this is also related to negative temperature, which he's also done a video on.
Ahhh...the red hot nickel ball days😢
Nice Open Sauce tshirt, hope I can make it one year
Nice video. 🖖
You can heat metallic things with "radio wave" frequencies using induction furnace...
Fun fact: Because of the definition of temperature (which only makes sense in macroscopic systems, as it deals with the entropy concept) T=dQ/dS, in systems where there is a maximum energy there are states where temperature is negative. Additionally these negative temperature bodies always transfer heat to positive temperature bodies. A good example of a negative temperature system is a laser 🤯🤯🤯
I love watching dirk nowitzki doing science
This was very interesting ❤❤❤❤❤
me watching the laser cut steel like butter then this guy suddenly tell us about electric toothbrush
Peak promotion
Imagine if all 4.6 million subscribers shined a laser in the same spot.
When two coherent laser beams destructively interfere with each other (like in the LIGO detector), where does the energy go?
My dumb ass waiting for the infrared card to glow💀:
If I rub my hands, both get hotter than my hands! Have I violated any law of thermodynamics, or is it just work used to increase the thermal energy?
Mechanical work converted to heat by friction. Just like what brakes do.
I guess the infrared temperature sensor has provision for ignoring emission lines, so it just ignored the laser light being shone at it.
National ignition facility... Hold my beer.
What happens if you get like a spherical array of those laser cutters or even stronger lasers, pointed them all inwards towards the direct centre of the sphere and then fire them at something in that centre point?
I believe that's the principle of the fusion reactor at NIF
It'll likely vaporize quite rapidly. It's basically a lower power version of one of the proposed methods of igniting fusion. Fuel is inserted into a pellet and it gets hit with high power lasers from multiple directions; the blast wave of the shell vaporizing compresses the fuel to fusion conditions.
Crazy that when you light a match, it gets hotter than the surrounding environment
I didn’t know light didn’t have a temperature. That’s actually been something I was wondering
Did you say that you cannot focus sunlight to a pinpoint that is hotter than the source?
If I have a very large surface at 1000 C, and I focus the light (IR) to a pinpoint, the pinpoint will not be hotter than 1000 C?
Yes, no hotter than 1000.
@@nuclearmedicineman6270 How would the pinpoint radiate the excess energy away?
No, you can't get it hotter than 1000C with just lenses and mirrors.
@@DANGJOS You don't help anyone by just repeating the statement. The Stefan-Boltzmann Law works with an area, the magnification(in one direction) has an effect for the equilibrium of the heat transfer.
Conservation of Etendue
Reading the title, I thought this is going to be about laser cooling.
THANK YOU, ACTION LAB! DOGE COIN GOING UP BABYY!!🚀🚀
So if I understand it correctly. The laser just turns the light energy into heat energy at the point of impact. The total energy of the light energy will be more than the energy required to heat up the material by X amount. other will be lost in form of reflected light or other forms of energy. You literally said it. light has no temperature. so no paradox?
That water flosser looks cool, but it's really bulky. What if we could attach it to the faucet? I bet you wouldn't even need to put a motor in it to get it up to pressure!
youre actually mixing up some stuff here, the magnetron of an microwave is not around 100 degrees. or rather the electrons in it are extremely hot by being pumped by electromagnetic fields, about 80 000 K (although measuring this in temperature is kinda pointless), above this a magnetron should not heat up anything. not normally a concern obviously but quite different from the negative temperatures that lasers have.
7:34 doesn't that mean you can heat an object more assuming you focus all of it on a smaller object since a smaller object won't radiate the heat as fast right?
Light can cast shadow, therefore there are limits to laser concentration.
wtf do you mean
is transfering enegy through lasers is more efficient
I know it doesn't need to be said, but lasers are really cool!
Thanks.
You can heat up the filament in your toaster to ~800°C even tho the steam in your powerplant is only around 400°C
The principle only applies to using lenses and mirrors and a hot body.
What confuses me is the sun is continually adding energy - it's an ongoing nuclear reaction continuously pumping more energy out in the EM spectrum - it's not coherent light like a laser, but there's not only the blackbody light radiation coming from the sun, but all of the photons generated by nuclear fusion as well - so it should theoretically be able to do what a laser pointer does a trillion times over.
What would happen to a graphite rod in vacuum chamber, when you shine laser on it?
Brighter than the sun.
question , If a laser runs for say 1 hour just pointed at nothing , say out to space , and you measure the lasers head body cavity temperature , Then under the same conditions , but , this time the laser is being used to say , cut metal , Would we measure the lasers body , or head, or cavity etc.. to be hotter ? In other words does a laser get hotter if its doing work ? has a load on it , compared to no load . Thank you very much.
Once the light is emitted from the laser, it does not interact with it anymore, whether it ends up hitting metal or nothing, the laser has no "idea" what happened to it because the information does not come back.
One exception would be if some light is reflected off the metal and comes back to hit the laser, heating it up, but considering your question I think this is a technicality
@@Jules.D Thank You for replying , And so quickly . That is what I suspected . I'm too lazy today LOL!
I want to see more of that super lazer is that what comes out of superman
Cool!
Next: how laser can cool down things! Much more interesting topic
So where exactly is all this vaporized metal condensing?
Laser dust, aka metal dust. The exhaust is drawn into an air handler. If you want mars soil, ask for some laser dust. It's nearly the same density of air. Gets everywhere. Probably giving me Parkinson's in a few years.
To be pedantic; single particles or atoms do not have a temperature. Temperature is an emergent phenomenon categorized by the aggregate motion of the particles in the system.
then how a scientist got noble prize by inventing a method to cool down SINGLE ATOMS to just a few milli Kelvin above absolute zero
I am confused, wouldn’t there have to be a limit to temperature, otherwise the particles would end up vibrating faster than the speed of light.
I think the rough answer is that the kinetic energy of the particles goes up faster than the speed. This is because the relativistic mass of the particles goes up with their speed. To reach the speed of light the particles would need to be infinitely heavy - which never happens. In a sense the energy creates extra mass. E = mc^2 comes in here somewhere, I think my explanation is basically correct, but probably no use the latest way of explaining it.
What laser?
Some say the sun isnt a thermonuclear heat source but a electric discharging node in the galaxie
Because it is an Electric Universe...
One is a stationary source of energy. On the other case you are continuously pumping and dumping energy.
So the best strategy is the pump and dump scheme, got it
Is it possible to have an objects temperature so hot its black body radiation is averaged well beyond the visible light spectrum rendering it 'invisible' (well black)
@7:35 did Einstein say this too? Let's go scientists trolls. No he didnt
Weird how the universe is. Unrelated to this I had bought a radioscope the other day. Testing my LEDSs of different wavelength.
So If I use a match 600'C to light a piece of wood in the forest, generating a huge fire reaching 2000C'
You'll see that with a single source of lower energy I generated MORE energy
😂😂😂😂😂
The match does not PRODUCE the energy of the forest fire, it is just something that starts a process.
Thermography cameras have sensors registering radiation in the range 7000-14000 nm. There is no reason at all why an infrared laser at 989 nm should register on such a camera. It is just like wondering why you can't see blue with a red filter before your eyes.
This is crazy
Unfortunately lasers cannot get very hot
I wonder if itd be meaningful to do a "How hot is electricity" spin off?
It's really disheartening to see the false analogy you used of sunlight thru a magnifying glass & laser light.
Light is just a method of energy transfer so the proper analogy would be the power input (battery chemistry/electrical potential) of the laser vs the Sun's surface energy (the atomic/subatomic reactions that power it) to the magnified beam.
Therefore it would be more correct to say the heat generated by a laser can be no more than the total power of the energy source powering it.
If one put a short across the lithium battery source (or the building's electrical lines) they would reach an equivalent temperature rating.
He is talking about limitations on temperature produced, not about limitations on total energy or power. Temperature changes have some relation to energy and power, but they are not the same thing.
I don't think he was using an analogy, but a comparison.
Learned something? Yeah, lasers are cool..... and hot.
Next: laser cooling
The video feels incomplete, light goes in and the light-matter interaction is where all the black box magic lies, but this video didn't explain that. Would that same laser melt me up like it did the metal? Why or why not? How does the energy of the laser get converted into thermal energy? The material absorbs it, and how much it's absorbed is material-dependent, why? What's the difference between a continuous wave laser and a pulsed laser?
Hmm ... that's against my intuition 🤨
imagine we use a lens with an area of, lets say, 10 square meter, and focus all the light on a grain of sand (which is insulated within a thermos can by the way), then the grain gets so much more energy compared to its size
Would it still not get hotter than the sun? Where does the focused energy go then?
If the heat radiation can get in (into the thermos) then it can get out. As the grain of sand gets hotter, it radiates energy away.
Water flosser are this, days like brushes not anymore only like your stone age version.
I wanted to see something blow up.
It's getting hot here
Ooooooooooooh, I'm blinded by the lights
Wave length decreases energy increases then why infrared and microwave is more powerful than visible
They aren't. Microwave ovens are usually in the range of about 1000 watts. Modern household LED lightbulbs are on the order of 10 or 20 watts. Light fixtures also tend to disperse the light rather than focus or contain it within a small space. Even if you used a 1000-watt LED light fixture and focused all of its light on a single object, it won't heat up as quickly unless it's black because it'll be reflecting a considerable portion of the light. Microwaves and infrared tend to be readily absorbed by most substances, particularly water and oil (major components of most food). High energy light tends to penetrate objects rather than be absorbed, this is how x-rays can be used to image bones, most of the light passes right through flesh without being absorbed.
How powerful Woolley this laser be of it was 100,000 wts
If you like lasers - watch the last Mark Rober video
As Leonard Nimoy would say...
Dang I am early to a video.
Imagine how clean your teeth would be if you used that 10 kilowatt laser.. 🦷😊👍
Of course focusnig sunlight can heat up material hotter than the surface of the sun... imagine focusing the suns entire radiation output onto a penny... you reall expect it to only heat up to a few thousand degrees?
Syropyro got ch beat
the second law does not guarantee
it suggests
If the probability of anything else is basicly zero you are basicly guaranteed it will happen.
Gamblers are guaranteed to lose money in the long run, its not just suggested by statistics. And if you won money, you just didn't play long enough.
Watt for watt will always true tho
Hello 👋🏻👋🏻👋🏻👋🏻
What’s the highest temperature anything in the Universe has reached? Was it during the Big Bang?
"you can see it on this infrared sensor card"... does nothing.
How nice it must be to have teeth.
So then why?
The 'confusion' comes from Dunning-Kruger people not understanding the difference between light, EM radiation, temperature, and energy.
Bri what are you trying to say?
Hawk Tuah
Made in Germany 😁