If Ultra Violet Photons have higher energy, why do lower energy Photons transfer heat. It seems a bit counter intuitive. Or why don’t Ultra Violet Photons carry heat as well?
@@kadourimdou43 I believe it comes down to the fact that photons have to deliver ALL of their energy rather than just a portion. Thermal infrared photons have energy levels close to what's required to makes the bonds of molecules, or the molecules themselves, vibrate and so "carry" heat. Ultraviolet photons, on the other hand, have enough energy to actually break bonds so smash through rather than produce vibrations.
@@kadourimdou43 All photon radiate heat. The stuff around us is "cold" so it only radiate low energy photon (infrared) hotter stuff radiate visible photon (red hot steel rod, hot charcoal, the sun) and even hotter stuff radiate ultra violet. Look up black body radiation if you want to know more, it explain the relation between the type of photons radiated and the temperature.
Thermal engineer here:) 2 fixes to help. One paint the rods and or plate. The emissivity of the metal is too low so the thermal camera can't accurately calculate the temperature. Paint emissivity is around 95% so it's a trick we use to get an accurate reading. At infrared wavelengths aluminum is basically a mirror. Two is put a thermal compound between the rods. You are probably having a huge contact resistance between them that is preventing the heat from flowing. Awesome videos!
@@ScienceAsylum I’m pretty sure perfection clone will coerce you into making a follow-up video explaining the phenomena that didn’t work out the way experiment clone would’ve liked. 😉
@@redactedbananas peanut butter would actually be better. The heat capacity of water would act like a heat sink - drawing heat from the hot rod, while simultaneously not passing it on to the cold rod.. Peanut butter better! 😉
Just know that “infrared” is still a spectrum of wavelengths. The camera you were using “views” a very narrow wavelength of infrared which reduces it’s capabilities. This greatly reduces the cost and complexity of the design. The ones I worked on in the military could “see” things in a way that you simply wouldn’t believe. The list of materials that are permissive to some part of the spectrum is rather impressive.
you talking about millimeter wave technology? we've been hearing about that shit for about 20 years so I assume they're at least three generations ahead of it by now
To have a more accurate representation of the temperature of a metal through an infra-red camera it is necessary to paint the metal or to cover it with tape ... !!!
@@kingmasterlord I would assume the level of definition has changed drastically since I was in. I remember two pictures I kept on the wall in my workshop. One was an empty chip bag floating in the ocean taken from 20 miles out at night. The label could be read, too - Doritos! The other picture was of a “grain” hauler taken in the middle of the day. The silhouettes of the illegal military choppers it was carrying in the cargo hold were clearly visible through the side of the hull. This was in the 80’s!
So the thing about metals is that their emissivity is low and reflectivity is high. That jacks up their blackbody spectrum, which probably confuses the camera. I learned this by putting a hot silver (real silver) dollar in a thermal image and it looked ice cold.
It also depends on the specific metal you use. Iron has emissivity reasonably close to 1, which is what most thermal imaging assumes in calculating the temperature from Stefan-Boltzmann law. The value is also close to most materials such as plastics and organic matter. Aluminium - depending on the finish - can go as low as 0.2. I first encountered this issue when locating aluminium heaters with cheap thermal cameras.
@@TiananmenSquareMassacre1989 Well in general with metals, it heavily depends on the surface, its roughness, corrosion layers, etc, much more than what metal it even is. Practically, the only 'quick' solution is to discard ALL readings of direct metal surfaces, and paint/otherwise cover all metal surfaces you want to measure. Everything else requires you to painstakingly measure points with a regular thermometer, correct for the discrepancy, and then avoid any movement relative to the camera, which obviously limits what you can do massively.
Use the camera on: • the sun on a clear day • the bottom of clouds that are blocking the sun • the exhaust of car (if gas powered) • rubbing together stuff to test friction • a sideways view of heat when you breath out with mouth pursed to cool down stuff vs mouth more open to warm up stuff
the sun just looks like a point of heat in the sky but looks cool through trees, you can see clouds that are different temps and lower, because they are cooler, the exhaust move really fast from engines and you cant really see it unless it has particles like smoke or flame to see but the pipe and anything getting hit by the ehaust can be seen(thin fiberglass airfilter mesh from a house ac in front of the pipe lets you see the air better), as soon as yoyu start rubbing and the heat is obvious and grows in brightness on most things, the vapor from your mouth when compressd can bee seen a tyny bit since you are seeing the particles and they are usually 98f ish vs the air, the air you breath out is pretty warm, the pursing makes a slimmer stream that is a little cooler but mostly still warm :)
5:30 You’re definitely making us engineers feel better about ourselves. We may not be the best mathematicians or physicists but we know how to do buildy stuff.
Great video! I have one comment and one question. (1) you mention our eyes see only a narrow band of EM wavelengths. That narrow band is also those wavelengths that transmit through water. A professor I had (Arthur Swift) once observed that this is not a coincidence, since the human eye is mostly made up of water, and an eye that cannot see is useless. (2) Now for the question. I was told that there are three partial differential equations of classical theoretical physics: the wave equation, the Laplace equation and the heat equation. Furthermore, these equations are distinguished by what partial derivatives appear, and what order these are. The properties of the heat equation arise from that equation having a first-order partial derivative with respect to time. Now I seem to recall that the Schrödinger equation also has a first-order partial derivative with respect to time. Yet everyone calls the Schrödinger equation a WAVE equation. That makes me wonder. Is the Shrödinger wave equation really a heat equation? Or does the appearance of complex numbers in the S.E. mean all bets are off?
It's true the Schrödinger equation isn't _really_ a "wave equation" in the strictest sense. I've never thought about it being a heat equation though. that's an interesting thought.
"I'm pretty sure that's Homer Simpson in the oven, rotating slowly. His body temperature has risen to over 400 degrees, he's literally stewing in his own juices"
Unless they are reflecting heat coming in from something hot. Metals also have huge reflectivity and even a remotely smooth piece of metal will act as a mirror to IR.
Explains a lot why the inside of a car gets so hot: the IR radiation can't escape as well as the llight can enter! Well, of course, that's the greenhouse effect, but it's still cool to see it from other points of view
When you was sawing that rod clamped on that wigly tablet i started laughting so hard. Is so funny to see how some people just forget all the theories they should know so well when they need to apply to real world. Sad fact reality Is not a controlled environment. That cheap clamp on that flimsy and wiggling table to "help" sawing an aluminum rod was the peak of this.
To get good heat conduction from the hot rod to the cool rod, you need a good surface finish! A hacksaw finish will only put a tiny fraction of the surface area in contact, and the rest will be air. A good thermal interface material (such as silver-filled thermal paste commonly used inside computers) will make a big difference too.
I put in a link to Engineering Toolbox and my last comment seems to have disappeared. The problem you have with the rod is thermal emissivity. This is the reason why the clamp _appeared_ to be warmer. Bare aluminum with a thermal emissivity coefficient of (0.03-0.07) is one of the worst materials you could have chosen. When measuring a metal surface with a infrared thermometer, they tell you to aim at a painted surface or apply some tape to use as a target.
Thanks for the feedback. That's helpful. (I have YT set up to block links. They usually go into my "held for review" list and I can approve the acceptable ones, but I can't find yours in there to approve it. Weird.)
@@ScienceAsylum You get a new video out of this explaining emissivity vs. reflectivity. And you can explain it in terms of wavelength and choice of materials for the JWST mirror. Win-win.
Probably the case of the rod to rod may be the imperfections due to the cuts, if you didn't polish them a bit, there are small air spaces that isolate the heat flow between them since the conductivity of air is very low and the space way not be big enough to have effective convection. That's basicaly what happens in isolating windows.
Yes, the rough cuts made with a HAND HELD HACKSAW are probably the primary cause for the failure. The contact between the two rods was probably microscopic. Just the high points, and I use the word points advisably, are all that could possibly touch the other rod. When you consider that both rods have those high points, you get almost zero contact area. In electronics we use aluminum heat sinks to dissipate the heat generated in some components, like power, output transistors or FETs or computer processors. A heat sink compound is almost always used between the component and the aluminum heat sink. These compounds are like putty in their consistency, but are formulated to be good conductors of heat. And they conform to the surfaces of the component and the heat sink. So maximum heat can be transmitted. If you tried the aluminum rod experiment again but with some heat sink compound between the ends, you would probably get much better results. Of course, another way would be to mill the two ends flat and then polish them to remove the tool marks. But even then, you would need a lot of pressure between the two rods to actually achieve good contact. The heat sink compound is a much better way.
5:37 - The ends of your rods are so rough that you have only couple of point(like) contacts between them. You would need a lathe and probably even polish the two ends to have a good approximation of ideal connected rods. Or you could try using some heat conducting paste between them, but the heat conductivity of the paste should be better than the heat conductivity of your rods.
@@ScienceAsylum The two ends could be held together with a little tape without affecting the result of the experiment too much, because even if the ends are polished smooth, if you're holding it, they'll not connect well. Yes the tape would absorb some heat but not enough to invalidate the results.
Another suggestion for using the thermal camera. It might be possible to manualy adjust what the range of the color grading is (sometimes even in post). Allowing you to make it wider, narrower, or specifically cut off at a certain temperature. Using these techniques you can make it easier to detect specific changes, or make a gradient easier to visualize. Say for example in your shot with the metal shelf, the ground showed at the cold end of the range. If you could had clamped the coldest point of the image to 1-2C below the temperature of the shelf, the ground (which was not part of the experiment and therefore less intersting) being colder than that would just be black, and the shelf would show the dark blue instead of the yellow or Hot. Then either lock the high end somewhere with enough headroom to see the change you are expecting, or it might allow that point to auto range with the rod. Although on the version of the device and software you have these features might not be supported. Not to take away from the additional information you tied in about diffusivity by changing the medium to wood. Another tech tip for imaging reflective objects, specifically aluminum, it is also quite good at reflecting IR light, and can sometimes be challenging to get a clear image of it. This is typically more of an issue when you are trying to image a piece that is not the hottest thing around. Like for example trying to look at the temperature of your computers CPU cooler, you have a non zero chance of simplying getting your reflection instead of the actual temperature of the metal. Great video I'm sure you will find some other interesting things to show off once you've had more time with it!
8:36 My mind completely blew up! after "air is a fluid". I learn that I have a lot of misconceptions throughout your videos, Thanks Nick! I have language issues when learning physics, for example, heat and temperature are both called the same word.
Ok, ideas for the thermal camera... 1. Liquid nitrogen spill 2. Pot of boiling water, preferably in a cold open environment 3. The cabinets and walls around an oven when it's on. 4. HVAC outlets, can you see where the air flow is going? 5. Compost pile 6. Different types of LED bulbs and fixtures 7. A cooler full of ice on a hot day, are there cold spots where heat is getting in? 8. Two metal balls impacting at moderate velocity, this can burn a small hole in a piece of paper, can you capture the moment? 9. Triboluminescence, crush wintergreen life savers, does it produce heat as well as light? 10. An electric vehicle at a supercharging station
Was just about to do a video on these basic concepts for my students. You have just saved me loads of time and done it better than me as usual 😊. If you need to borrow any cutting tools in future let me know 😂👍
I got the thermal camera for the usual job of checking for leaks and insulation. It turned out to be much more useful with puppy toilet training to find any accidents on dark carpet. Go outside at night time and you'll see just how much thermal energy all the roads and foot paths hold, they light up over everything else
Seeing heat output of everyday items could be neat. Such as showing the heat outputted from your refrigerator, or maybe comparing an old TV to a new one.
Nick, yet again Great work! Will definitely use it in my physics classes when I teach thermodynamics next year. Is the heat equation you show the same thing as Newton's law of cooling?
Nice video! But what you have completely ignored is the HEAT TRANSFER COEFFICIENT / thermal contact resistance - it is the beast in all heat calculations and indicates how well heat flows from one body (or fluid) to another. Another point: what you see brighter with a thermal imaging camera is not necessarily warmer, because EMISSIVITY.
@@ScienceAsylum I see. Nevertheless, the video is great. Thank you. 🙃 Also, I have to ciorrect myself. The heat transfer coefficient is not the beast in heat calculations - it's just a number you can assume or guess - but it's beast in all experiments where heat flows from one body/fluid to another body. Like in your experiment.
4:55 heat transfer problems can actually be rewritten using the formulas for electricity and converting various parameters to resistors and capacitors. I bring this up because the graph you show looks a lot like the falling edge of a signal on an oscope
My local city electric utility has (or used to have) an infrared camera for health-checking various electrical equipment. A lot of electrical faults slowly increase in resistance and start heating up before they actually fail, and a lot of money and downtime can be saved by identifying and replacing problem hardware before it hard-fails. Anyway, I suggested it because the visuals can be pretty cool. If you're still looking for targets for that infrared camera, you might point it at a few electric boxes around your area, the higher-power the better. Maybe stop by a substation. Needless to say, if you see something that looks unusually hot compared to similar items around it, it would be helpful to contact the utility and send them an image!
a thermal transfer medium might help also. ie thermal paste or since this is hot; liquid metal. you are getting air trapped between the rods and plate. air transfers heat poorly
Try thermal compound to couple the rods like how we attach heat sinks to discrete power devices. Maybe hold the rods in place with a wooden apparatus/clamp/cradle, whatever.
i still recall the school experiment we did to show conduction: a long steel rod held in a clamp, with soft wax blobs attached at regular intervals, and a bunsen burner applying heat to the far end. as time passed, and the heat conducted, each blob of wax would fall off in turn
"There is no such thing as a truly adiabatic container" can also be read as "There is only the wave function of the entire universe". Thermodynamics is profound like that.
Or as Fourier was claimed to have said, "Any periodic function can be represented by a combination of sines and cosines. And with enough imagination, anything in the universe can be considered 'periodic'." :)
Conduction duction, what's your function? Another issue that prevented the flow of heat from one aluminum rod to the other quickly was the poor mating surface between the two allowing for more air to act as an insulator between them thus further slowing the heat transfer.
i got seeing the heat fixtures through the walls of your house, i even understood the thermal imprints footprints, but the idea that you couldn't see heat threw a window somehow still blew my mind :P in retrospect from watching your video, it makes total sense.
Used a thermo camera on a parking lot once, it was cool that suddenly you could see which cars had recently arrived by the temperature of their wheels.
Oh boy 🙄. As an engineer, I'm greatly tempted to ridicule theoretical physicists' inability to experimentally prove their own results. But don't worry, I'll control myself. In fact, I actually liked this video for many reasons. The biggest lesson is that practice is much more difficult than theory.
An new video idea: In this one, you touched on the 3 heat transfer methods used for macro scale calculations. I think it would be cool if you explained how heat is really transferred via photons. In other words, the particle physics version of heat transfer.
The lines that are shown in some of your thermal images have been added by an additional process that could use some explanation. For example, Teledyne has a system that combines some visual content with thermal images (edge detection): "FLIR MSX® (Multi-Spectral Dynamic Imaging) adds visible light details to thermal images in real time for greater clarity, embedding edge and outline detail onto thermal readings."
Even dull metal acts like a shiny mirror at IR wavelengths, and radiation is minimal. A thin stripe or small dots of paint or tape, along the length of the bars will show their temperature a lot better, plus join them with a thin layer of thermal paste, (or oil, water, jam... ) to conduct better. The heat the camera picks up from the bar itself is mostly the reflection from the environment unless it has high emissivity. Try looking at two teapots with hot water in them. One stainless, one ceramic. :-) Mmm. Tea.
Very fun video ! Also, you might wan to use thermal paste to make good contact beween your rods. That's what people do when they wan to put a heatsink (piece of metal) on a hot computer chip; so it's probably important.
Great video. Not sure what it was about because I couldn't stop laughing at your subtle humor. Been watching since you were a high school teacher. Keep up the good work.
Great video, however, I’d love to see a part two that goes into more detail and maybe addresses some of the problems you had pointed out by other commenters (thermal contact resistance, environment conditions, etc). Maybe you could do that classic demonstration of two separate volumes of hot and cold water mixing in a tub. That might look cool. (Btw im a huge fan and can’t wait to watch your videos when they come out. I’m an engineer and generally have somewhat of a good grasp on the topics in your videos, but you always give me valuable insights i never knew existed. )
Getting into custom loops and water cooling has taught me that the surface contact between the two rods is going to matter a great deal with heat transfer as air is a great insulator even in extremely small pockets. You should consider sanding and polishing the ends of both rods, and using thermal paste between the two.
I use a flir thermal camera to do fast diagnostic on older diesel engines with a misfire, cooling system issues and electrical issues like high resistance in wiring or control equipment issues that need a fast diagnostic with the right set of symptoms.
You should film your rods against a cold background, I suggest a large flat tray that you've put in the freezer for a while. Fill the tray with water and let it freeze. This will give you a large cold background. Stand the tray on polystyrene blocks to insulate it from the ground, so the ice will take longer to melt. Use a grinding wheel to polish the ends of the rods so that they make good thermal contact. Use a blob of thermal heatsink paste between the ends of the rods to improve the thermal contact. Film from above, in the shade.
Check your circuit breaker panel with the outer cover removed. They do this annually at shops to detect bad, overheating breakers before they melt down.
I have to get in there soon for something else anyway. If I remember, I'll check then. I'd be surprised if the inspector didn't check it though. (He's my wife's dad, so he went the extra mile for us.)
"If I touch the wall for a bit, and remove my hand..." Wow! That's serious dedication to science. Nice to see the prosthetic replacement is indistinguishable from your original!
7:43 you are not taking into account the emissivity of the rod, which (given it looks shiny) is very low, around 0.01. This means the detector in the camera will not pick up the temperature of the rod but will the clamp as the clamp has paint on it. Paint of any colour has an emissivity from 0.8 to near 1.
@@ScienceAsylum Hi, all you need to do, I think, is paint or put tape on the bars so the camera's detector (microbolometer) measures/detects the heat. Buy or borrow a silver bar or coin as it has the highest thermal conduction. Cool.
Why water can freeze if it sees space. Everything is constantly radiating energy out in every direction. So why doesn’t everything constantly cool down. The objects around an object are radiating at the same rate (if they are all the same temperature) So set a book on a desk next to a wall. The book radiates energy toward the wall. At the same time the wall is radiating the same amount of energy back at the book. Same thing with the ceiling. The book is radiating energy toward the ceiling and the ceiling is radiating toward the book. Now put a pan of water in the middle of your yard at night with a perfectly clear sky. The water radiates energy toward the bottom of the pan and the bottom of the pan radiates energy toward the water. Same thing with the sides of the pan. Now the top surface of the water is radiating energy up but there is nothing above the pan of water radiating any energy back at the water. This is why I think a pan of water on a clear night with the temperature outside at 38 degrees Fahrenheit can freeze. Please correct anything I got wrong on this. I have seen it talked about but never seen anyone actually describe exactly why water can freeze like that.
Consider. The emissivity of the surface of a material is its effectiveness in emitting energy as thermal radiation. Shiny objects like aluminum (low emissivity) while hot to the touch may not appear hot on an infrared camera. The opposite of a black body. This may explain some of the issues with your experiment.
I love the FLIR camera! I have observed the best results by filming in the dark. When filming in infrared One must consider setting up the environment to get the best contrast. Also consider reflective surfaces etc. Infrared is still light (obviously 😅) and not as intuitive to work with. Always love your videos!
The end was great. As soon as I stated the video I said in my head. Smart man makes a video which makes money also gets a thermal camera which can then be used to conduct a thermal review of the house and its all a write off for business. 😅😀😀
I've never thought that much about how infrared cameras and mirrors work, and is kinda mindblowing. But then this video reminds me about thermal equilibrium and Heat Death and now I'm sad again.
That equation.... I think the main struggle people have with higher mathematics (the divergence symbol, partial differential symbol that looks like an upside down lower case "e") is that we expect people to not learn how to draw these symbols until college. All other symbols for math and language are taught way earlier in life, in grade school. To suddenly start inserting new symbols and expecting people to remember them and their meaning is, I think, a big reason why so many people do not go into science and engineering.
I have a professional thermal camera at my job, it has pretty accurate temperature measurements. Just some facts about thermal cameras: - shiny metal surfaces do not radiate heat in the range of the thermal camera. They act like mirrors and often 100C degrees of difference shows up as 5-10C degree. You need to apply paint or electrical tape to metal surfaces to be able to measure it. - some opaque plastics are completely transparent in IR range - farts do not show up on thermal camera :)) - surfaces of liquids are cooler than the liquid below, you can not trust the measurement
I’ve been contemplating thermal conductivity and stuff like that because I needed a dehumidifier and there was an old abandoned water cooler at the house I moved into, so I decided to chop the top off the stainless tank inside the machine and blow air into it so that it condenses on the sides where the coils are... which works but because the coils only cover about 1/3 of the tank it doesn’t actually accumulate all that much moisture before it cycles off and defrosts into the drain at the bottom of the tank and goes into a bucket. What I need to do is fill the area outside the tank where the coils are with something thermally conductive so that more of the tank gets cold, and then of course surround that with a layer of insulation to keep condensation from building up outside the tank. I was looking into materials and it seems like mercury would be the ultimate substance to use but obviously will not be since it’s extremely unsafe, so something more inert and commonly available will have to do... I’m thinking sand, but for some reason gravel has better conduction which is a bit confusing since it wouldn’t make very good contact... also sand conducts better with moisture in it, I suppose it makes sense since more contact conduction can happen... gotta give it a try, not sure how it would handle the expansion if it froze, but I guess I’ll see if that happens.
I'd be really interested in looking at very far away objects to see how much our atmosphere interferes with radiative heat. Or, if even possible, seeing how different the moon looks in IR over the visible range.
Just a heads up (and I could be wrong) just like visible light in the EM spectrum is emitted by electrons vibrating at a certain frequency w/ a certain wavelength, the EM waves emitted by objects along the infrared spectrum just so happens to correspond with the vibration/“frequency” of the atoms as a whole. Which is why it works to detect temperature
Some glass *reflects* IR quite well, which I usually rediscover when trying to measure something through a window... electronics (computer circuit boards especially) are educational to look at, I've used an older phone-based thermal camera to diagnose failed chips and motors in industrial equipment.
You should explain emissivity and why gloss and matte surfaces matter. I have burned my skin with polished alluminum because thermal camera showed 60 degr. C but it was 130 deg. C. Solution was to tape piece of paper to the gloss material and measure that to with the camera.
@@ScienceAsylum The problem with glossy surfaces is that camera measures the reflected temperatures and the surface temperature at the time. You will measure the mix of the both, depending how much is reflected to the camera. EVERY camera and even laser-pointer thermometers have setting for surface emissivity. Every time you measure something, you must first check that setting and change it according to the surface you will measure. Even with that done properly i find it better to have a masking tape with me all the time. The tape is thin and matte and it will show almost perfect mesurements.
I apologize for the terrible parallax offset in many of the thermal images. I didn't realize it was a problem until it was too late to fix.
Thanks for the clarification on what I was seeing
If Ultra Violet Photons have higher energy, why do lower energy Photons transfer heat. It seems a bit counter intuitive. Or why don’t Ultra Violet Photons carry heat as well?
@@kadourimdou43 I believe it comes down to the fact that photons have to deliver ALL of their energy rather than just a portion. Thermal infrared photons have energy levels close to what's required to makes the bonds of molecules, or the molecules themselves, vibrate and so "carry" heat.
Ultraviolet photons, on the other hand, have enough energy to actually break bonds so smash through rather than produce vibrations.
Appreciate you acknowledging it
@@kadourimdou43 All photon radiate heat. The stuff around us is "cold" so it only radiate low energy photon (infrared) hotter stuff radiate visible photon (red hot steel rod, hot charcoal, the sun) and even hotter stuff radiate ultra violet. Look up black body radiation if you want to know more, it explain the relation between the type of photons radiated and the temperature.
Thermal engineer here:)
2 fixes to help.
One paint the rods and or plate. The emissivity of the metal is too low so the thermal camera can't accurately calculate the temperature. Paint emissivity is around 95% so it's a trick we use to get an accurate reading. At infrared wavelengths aluminum is basically a mirror.
Two is put a thermal compound between the rods. You are probably having a huge contact resistance between them that is preventing the heat from flowing.
Awesome videos!
Thanks for the feedback!
@@ScienceAsylum I’m pretty sure perfection clone will coerce you into making a follow-up video explaining the phenomena that didn’t work out the way experiment clone would’ve liked. 😉
THermal copound is really important. Its why CPUs need thermal paste, because 2 metals "touching" still have a giant airgap between them.
@@ScienceAsylum you could just use water as a thermal compound, in this case.
@@redactedbananas peanut butter would actually be better.
The heat capacity of water would act like a heat sink - drawing heat from the hot rod, while simultaneously not passing it on to the cold rod..
Peanut butter better! 😉
Just know that “infrared” is still a spectrum of wavelengths. The camera you were using “views” a very narrow wavelength of infrared which reduces it’s capabilities. This greatly reduces the cost and complexity of the design. The ones I worked on in the military could “see” things in a way that you simply wouldn’t believe. The list of materials that are permissive to some part of the spectrum is rather impressive.
i do not believe
Whoa!!
you talking about millimeter wave technology? we've been hearing about that shit for about 20 years so I assume they're at least three generations ahead of it by now
To have a more accurate representation of the temperature of a metal through an infra-red camera it is necessary to paint the metal or to cover it with tape ... !!!
@@kingmasterlord I would assume the level of definition has changed drastically since I was in. I remember two pictures I kept on the wall in my workshop. One was an empty chip bag floating in the ocean taken from 20 miles out at night. The label could be read, too - Doritos! The other picture was of a “grain” hauler taken in the middle of the day. The silhouettes of the illegal military choppers it was carrying in the cargo hold were clearly visible through the side of the hull. This was in the 80’s!
So the thing about metals is that their emissivity is low and reflectivity is high. That jacks up their blackbody spectrum, which probably confuses the camera. I learned this by putting a hot silver (real silver) dollar in a thermal image and it looked ice cold.
You can even use any flat piece of metal as a mirror for infrared light. By the way a copper sheet works very well for this and is not as expensive.
It also depends on the specific metal you use. Iron has emissivity reasonably close to 1, which is what most thermal imaging assumes in calculating the temperature from Stefan-Boltzmann law. The value is also close to most materials such as plastics and organic matter. Aluminium - depending on the finish - can go as low as 0.2. I first encountered this issue when locating aluminium heaters with cheap thermal cameras.
@@TiananmenSquareMassacre1989 Well in general with metals, it heavily depends on the surface, its roughness, corrosion layers, etc, much more than what metal it even is.
Practically, the only 'quick' solution is to discard ALL readings of direct metal surfaces, and paint/otherwise cover all metal surfaces you want to measure. Everything else requires you to painstakingly measure points with a regular thermometer, correct for the discrepancy, and then avoid any movement relative to the camera, which obviously limits what you can do massively.
@@TiananmenSquareMassacre1989 Iron has a high emissivity? Are you sure that's not anodized or something?
Pretty trivial to correct by applying a Matt black surface finish. Paint and even some tapes work pretty well.
Use the camera on:
• the sun on a clear day
• the bottom of clouds that are blocking the sun
• the exhaust of car (if gas powered)
• rubbing together stuff to test friction
• a sideways view of heat when you breath out with mouth pursed to cool down stuff vs mouth more open to warm up stuff
the sun just looks like a point of heat in the sky but looks cool through trees,
you can see clouds that are different temps and lower, because they are cooler,
the exhaust move really fast from engines and you cant really see it unless it has particles like smoke or flame to see but the pipe and anything getting hit by the ehaust can be seen(thin fiberglass airfilter mesh from a house ac in front of the pipe lets you see the air better),
as soon as yoyu start rubbing and the heat is obvious and grows in brightness on most things,
the vapor from your mouth when compressd can bee seen a tyny bit since you are seeing the particles and they are usually 98f ish vs the air, the air you breath out is pretty warm, the pursing makes a slimmer stream that is a little cooler but mostly still warm
:)
@@MrPruske Nice thanks! Am wondering if you meant the sun looks cool through trees as in 'a cool thing to behold' or as in 'a cooler temperature'? 😄
@@localverse That is, both.
5:30 You’re definitely making us engineers feel better about ourselves. We may not be the best mathematicians or physicists but we know how to do buildy stuff.
Problems are better solved with a diverse group of people. Engineers are necessary just as much as physicists and mathematicians 👍
as a failed combination of both groups atleast I saw this one coming a mile away.
Great video! I have one comment and one question.
(1) you mention our eyes see only a narrow band of EM wavelengths. That narrow band is also those wavelengths that transmit through water. A professor I had (Arthur Swift) once observed that this is not a coincidence, since the human eye is mostly made up of water, and an eye that cannot see is useless.
(2) Now for the question. I was told that there are three partial differential equations of classical theoretical physics: the wave equation, the Laplace equation and the heat equation. Furthermore, these equations are distinguished by what partial derivatives appear, and what order these are. The properties of the heat equation arise from that equation having a first-order partial derivative with respect to time. Now I seem to recall that the Schrödinger equation also has a first-order partial derivative with respect to time. Yet everyone calls the Schrödinger equation a WAVE equation. That makes me wonder. Is the Shrödinger wave equation really a heat equation? Or does the appearance of complex numbers in the S.E. mean all bets are off?
It's true the Schrödinger equation isn't _really_ a "wave equation" in the strictest sense. I've never thought about it being a heat equation though. that's an interesting thought.
Great point about the human eye
I decided to turn this into a video: czcams.com/video/LFC2HsT6Bh4/video.html
"I'm pretty sure that's Homer Simpson in the oven, rotating slowly. His body temperature has risen to over 400 degrees, he's literally stewing in his own juices"
Solid reference
Nick, I love the way you explained the heat equation! The growing and shrinking variables was very intuitive! 💜
My favorite "Stud" in your studio is YOU! Thanks for always WARMING up my day and RAIDIATING knowledge in an hilarious way!
One thing you missed is that metals typically have a low emissivity, so they tend to look "colder" on thermal cameras than other materials
Unless they are reflecting heat coming in from something hot. Metals also have huge reflectivity and even a remotely smooth piece of metal will act as a mirror to IR.
The fact that windows are sort of opaque in ir, is a kind of thing that everyone should know for better comprehension about universe
Explains a lot why the inside of a car gets so hot: the IR radiation can't escape as well as the llight can enter! Well, of course, that's the greenhouse effect, but it's still cool to see it from other points of view
So is it opaque because we make it that way for energy conservation of our rooms? Or is this a normal property of glass?
@@jpt3640 That's an interesting question!
@@jpt3640 I'm pretty sure it's just a normal property of glass.
@@pedroff_1 yeah!
Haha and it is like the principle behind the columbia’s omni heat coats 😅 sort of…
I really appreciate that you gave us the low quality experiment, and explained why it was unsuccessful. It helps me persevere in face of failure
Thanks. It's an important story to tell.
When you was sawing that rod clamped on that wigly tablet i started laughting so hard.
Is so funny to see how some people just forget all the theories they should know so well when they need to apply to real world.
Sad fact reality Is not a controlled environment.
That cheap clamp on that flimsy and wiggling table to "help" sawing an aluminum rod was the peak of this.
To get good heat conduction from the hot rod to the cool rod, you need a good surface finish! A hacksaw finish will only put a tiny fraction of the surface area in contact, and the rest will be air. A good thermal interface material (such as silver-filled thermal paste commonly used inside computers) will make a big difference too.
I put in a link to Engineering Toolbox and my last comment seems to have disappeared.
The problem you have with the rod is thermal emissivity. This is the reason why the clamp _appeared_ to be warmer. Bare aluminum with a thermal emissivity coefficient of (0.03-0.07) is one of the worst materials you could have chosen. When measuring a metal surface with a infrared thermometer, they tell you to aim at a painted surface or apply some tape to use as a target.
Thanks for the feedback. That's helpful.
(I have YT set up to block links. They usually go into my "held for review" list and I can approve the acceptable ones, but I can't find yours in there to approve it. Weird.)
@@ScienceAsylum You get a new video out of this explaining emissivity vs. reflectivity. And you can explain it in terms of wavelength and choice of materials for the JWST mirror. Win-win.
Nice introduction to transport phenomena as it was taught to me ~20 years ago. Wish i had a professor who explanined the matter like you did.
I was just thinking like half an hour ago I felt like I hadn't seen anything from y'all for a while. Good timing!
I took a week off after the entanglement video. Got to take breaks sometimes so I don't get burnt out.
Probably the case of the rod to rod may be the imperfections due to the cuts, if you didn't polish them a bit, there are small air spaces that isolate the heat flow between them since the conductivity of air is very low and the space way not be big enough to have effective convection. That's basicaly what happens in isolating windows.
Yes, the rough cuts made with a HAND HELD HACKSAW are probably the primary cause for the failure. The contact between the two rods was probably microscopic. Just the high points, and I use the word points advisably, are all that could possibly touch the other rod. When you consider that both rods have those high points, you get almost zero contact area.
In electronics we use aluminum heat sinks to dissipate the heat generated in some components, like power, output transistors or FETs or computer processors. A heat sink compound is almost always used between the component and the aluminum heat sink. These compounds are like putty in their consistency, but are formulated to be good conductors of heat. And they conform to the surfaces of the component and the heat sink. So maximum heat can be transmitted.
If you tried the aluminum rod experiment again but with some heat sink compound between the ends, you would probably get much better results.
Of course, another way would be to mill the two ends flat and then polish them to remove the tool marks. But even then, you would need a lot of pressure between the two rods to actually achieve good contact. The heat sink compound is a much better way.
Nick has found a way to put bloopers in the video, and I am loving it
5:37 - The ends of your rods are so rough that you have only couple of point(like) contacts between them. You would need a lathe and probably even polish the two ends to have a good approximation of ideal connected rods. Or you could try using some heat conducting paste between them, but the heat conductivity of the paste should be better than the heat conductivity of your rods.
Good point!
A drop of water would do the trick also.
I tried to file the ends down with my dremmel, but it didn't work as well as I had hoped. The job required better tools.
@@ScienceAsylum The two ends could be held together with a little tape without affecting the result of the experiment too much, because even if the ends are polished smooth, if you're holding it, they'll not connect well. Yes the tape would absorb some heat but not enough to invalidate the results.
@@ScienceAsylum Or you could just not cut the rod, heat one end, and watch it spread. And also paint it black to get a truer black body spectrum.
"Reality is complicated"... you are calling for an engineer 👏👏👏
I love the family work that you do, you picked the right person my friend.
cheers
Descriptions of equations Are so nice . Connecting maths with nature. Hope for similar videos in future
Another suggestion for using the thermal camera. It might be possible to manualy adjust what the range of the color grading is (sometimes even in post). Allowing you to make it wider, narrower, or specifically cut off at a certain temperature. Using these techniques you can make it easier to detect specific changes, or make a gradient easier to visualize. Say for example in your shot with the metal shelf, the ground showed at the cold end of the range. If you could had clamped the coldest point of the image to 1-2C below the temperature of the shelf, the ground (which was not part of the experiment and therefore less intersting) being colder than that would just be black, and the shelf would show the dark blue instead of the yellow or Hot. Then either lock the high end somewhere with enough headroom to see the change you are expecting, or it might allow that point to auto range with the rod. Although on the version of the device and software you have these features might not be supported. Not to take away from the additional information you tied in about diffusivity by changing the medium to wood. Another tech tip for imaging reflective objects, specifically aluminum, it is also quite good at reflecting IR light, and can sometimes be challenging to get a clear image of it. This is typically more of an issue when you are trying to image a piece that is not the hottest thing around. Like for example trying to look at the temperature of your computers CPU cooler, you have a non zero chance of simplying getting your reflection instead of the actual temperature of the metal.
Great video I'm sure you will find some other interesting things to show off once you've had more time with it!
8:36 My mind completely blew up!
after "air is a fluid".
I learn that I have a lot of misconceptions throughout your videos, Thanks Nick!
I have language issues when learning physics, for example, heat and temperature are both called the same word.
in my humble opinion, this is why the education system must be reformed.
Heat and temperature are not called the same word, at least not in English.
@@14jessek yep, im from Vietnam.
Ok, ideas for the thermal camera...
1. Liquid nitrogen spill
2. Pot of boiling water, preferably in a cold open environment
3. The cabinets and walls around an oven when it's on.
4. HVAC outlets, can you see where the air flow is going?
5. Compost pile
6. Different types of LED bulbs and fixtures
7. A cooler full of ice on a hot day, are there cold spots where heat is getting in?
8. Two metal balls impacting at moderate velocity, this can burn a small hole in a piece of paper, can you capture the moment?
9. Triboluminescence, crush wintergreen life savers, does it produce heat as well as light?
10. An electric vehicle at a supercharging station
You need to align regular camera and IR camera in the settings to show outlines of heat source image for better viewing.
Yeah, didn't learn that until it was too late.
Was just about to do a video on these basic concepts for my students. You have just saved me loads of time and done it better than me as usual 😊. If you need to borrow any cutting tools in future let me know 😂👍
I'm getting a hacksaw blade for my reciprocating saw. Shouldn't have to do this manually next time.
I got the thermal camera for the usual job of checking for leaks and insulation. It turned out to be much more useful with puppy toilet training to find any accidents on dark carpet. Go outside at night time and you'll see just how much thermal energy all the roads and foot paths hold, they light up over everything else
Urban heat island effect
Seeing heat output of everyday items could be neat. Such as showing the heat outputted from your refrigerator, or maybe comparing an old TV to a new one.
Nick, yet again Great work! Will definitely use it in my physics classes when I teach thermodynamics next year. Is the heat equation you show the same thing as Newton's law of cooling?
Nice video! But what you have completely ignored is the HEAT TRANSFER COEFFICIENT / thermal contact resistance - it is the beast in all heat calculations and indicates how well heat flows from one body (or fluid) to another. Another point: what you see brighter with a thermal imaging camera is not necessarily warmer, because EMISSIVITY.
Thermal effusivity did come up while I was researching this, but I decided that belonged in a different video. Could have been a bad choice though.
@@ScienceAsylum I see. Nevertheless, the video is great. Thank you. 🙃 Also, I have to ciorrect myself. The heat transfer coefficient is not the beast in heat calculations - it's just a number you can assume or guess - but it's beast in all experiments where heat flows from one body/fluid to another body. Like in your experiment.
4:55 heat transfer problems can actually be rewritten using the formulas for electricity and converting various parameters to resistors and capacitors. I bring this up because the graph you show looks a lot like the falling edge of a signal on an oscope
Interesting 🤓
that temperature change vs heat capacity analogy around @ 9:05 was perfect. It makes me better understand the concept. thanks
Glad I could help 🤓
My local city electric utility has (or used to have) an infrared camera for health-checking various electrical equipment. A lot of electrical faults slowly increase in resistance and start heating up before they actually fail, and a lot of money and downtime can be saved by identifying and replacing problem hardware before it hard-fails.
Anyway, I suggested it because the visuals can be pretty cool. If you're still looking for targets for that infrared camera, you might point it at a few electric boxes around your area, the higher-power the better. Maybe stop by a substation. Needless to say, if you see something that looks unusually hot compared to similar items around it, it would be helpful to contact the utility and send them an image!
Thank you for all you do for me and everyone.. I love your videos and you crack me up with the hotrod jokes.. You're the best man peace
a thermal transfer medium might help also. ie thermal paste or since this is hot; liquid metal. you are getting air trapped between the rods and plate. air transfers heat poorly
Yeah, the simulation was making a lot of subtle assumptions.
Drives me nuts as well, when I can't figure things out...So I watch you! 😊👍❤🇨🇦
Appreciate your hard work and educational video 🙏🏻
Try thermal compound to couple the rods like how we attach heat sinks to discrete power devices. Maybe hold the rods in place with a wooden apparatus/clamp/cradle, whatever.
I think that file then polish the end of the rods will also help
Best 80s music video ever!
Dude, you seriously need your own TV show. You need to educate the masses.
i still recall the school experiment we did to show conduction: a long steel rod held in a clamp, with soft wax blobs attached at regular intervals, and a bunsen burner applying heat to the far end. as time passed, and the heat conducted, each blob of wax would fall off in turn
"There is no such thing as a truly adiabatic container" can also be read as "There is only the wave function of the entire universe". Thermodynamics is profound like that.
Or as Fourier was claimed to have said, "Any periodic function can be represented by a combination of sines and cosines. And with enough imagination, anything in the universe can be considered 'periodic'." :)
Conduction duction, what's your function?
Another issue that prevented the flow of heat from one aluminum rod to the other quickly was the poor mating surface between the two allowing for more air to act as an insulator between them thus further slowing the heat transfer.
I tried to file the ends down with my dremmel, but it didn't work as well as I had hoped.
@@ScienceAsylum The ends should be totally flat and polished. Perhaps some heat conductive paste in between.
Otherwise this experiment will not work.
Mating surface 😂
i got seeing the heat fixtures through the walls of your house, i even understood the thermal imprints footprints, but the idea that you couldn't see heat threw a window somehow still blew my mind :P in retrospect from watching your video, it makes total sense.
Surprise!
Used a thermo camera on a parking lot once, it was cool that suddenly you could see which cars had recently arrived by the temperature of their wheels.
Interesting 🤓
@@ScienceAsylum …said the burglar 🦹🏻♂️
Oh boy 🙄. As an engineer, I'm greatly tempted to ridicule theoretical physicists' inability to experimentally prove their own results. But don't worry, I'll control myself. In fact, I actually liked this video for many reasons. The biggest lesson is that practice is much more difficult than theory.
An new video idea: In this one, you touched on the 3 heat transfer methods used for macro scale calculations. I think it would be cool if you explained how heat is really transferred via photons. In other words, the particle physics version of heat transfer.
The lines that are shown in some of your thermal images have been added by an additional process that could use some explanation. For example, Teledyne has a system that combines some visual content with thermal images (edge detection): "FLIR MSX® (Multi-Spectral Dynamic Imaging) adds visible light details to thermal images in real time for greater clarity, embedding edge and outline detail onto thermal readings."
Even dull metal acts like a shiny mirror at IR wavelengths, and radiation is minimal. A thin stripe or small dots of paint or tape, along the length of the bars will show their temperature a lot better, plus join them with a thin layer of thermal paste, (or oil, water, jam... ) to conduct better. The heat the camera picks up from the bar itself is mostly the reflection from the environment unless it has high emissivity. Try looking at two teapots with hot water in them. One stainless, one ceramic. :-) Mmm. Tea.
Hope you are feeling fine.. God bless you.. welcome back..
Very fun video !
Also, you might wan to use thermal paste to make good contact beween your rods. That's what people do when they wan to put a heatsink (piece of metal) on a hot computer chip; so it's
probably important.
Great video. Not sure what it was about because I couldn't stop laughing at your subtle humor. Been watching since you were a high school teacher. Keep up the good work.
I really do enjoy your programs.
Thanks! This one didn't do as well as I would have liked, but oh well. It was fun to make regardless.
Great video, however, I’d love to see a part two that goes into more detail and maybe addresses some of the problems you had pointed out by other commenters (thermal contact resistance, environment conditions, etc). Maybe you could do that classic demonstration of two separate volumes of hot and cold water mixing in a tub. That might look cool. (Btw im a huge fan and can’t wait to watch your videos when they come out. I’m an engineer and generally have somewhat of a good grasp on the topics in your videos, but you always give me valuable insights i never knew existed. )
I'm considering how to do a proper follow-up video for this.
Good to see you following Betteridges's Law of Headlines: If the headline ends in a question mark, you can usually just say "NO". You did.
The way you explain science concepts , I am sure that a video on "Schrodinger cat" will be a treat to watch . :)
Getting into custom loops and water cooling has taught me that the surface contact between the two rods is going to matter a great deal with heat transfer as air is a great insulator even in extremely small pockets. You should consider sanding and polishing the ends of both rods, and using thermal paste between the two.
thanks for your efforts ☺️
I use a flir thermal camera to do fast diagnostic on older diesel engines with a misfire, cooling system issues and electrical issues like high resistance in wiring or control equipment issues that need a fast diagnostic with the right set of symptoms.
Interesting 🙂
You should film your rods against a cold background, I suggest a large flat tray that you've put in the freezer for a while. Fill the tray with water and let it freeze. This will give you a large cold background. Stand the tray on polystyrene blocks to insulate it from the ground, so the ice will take longer to melt. Use a grinding wheel to polish the ends of the rods so that they make good thermal contact. Use a blob of thermal heatsink paste between the ends of the rods to improve the thermal contact. Film from above, in the shade.
Check your circuit breaker panel with the outer cover removed. They do this annually at shops to detect bad, overheating breakers before they melt down.
I have to get in there soon for something else anyway. If I remember, I'll check then. I'd be surprised if the inspector didn't check it though. (He's my wife's dad, so he went the extra mile for us.)
Increase the contact surface area for quicker diffusion,
Put the rods in contact length wise instead of radially.
As someone that plays oxygen not included, I approve this message. And recommend a follow-up about heat transfer systems they are really fun.
I think vacuum tubes (or valves for British people) in use could be great on thermal camera and to see the conversion cooling
"If I touch the wall for a bit, and remove my hand..." Wow! That's serious dedication to science. Nice to see the prosthetic replacement is indistinguishable from your original!
7:43 you are not taking into account the emissivity of the rod, which (given it looks shiny) is very low, around 0.01. This means the detector in the camera will not pick up the temperature of the rod but will the clamp as the clamp has paint on it. Paint of any colour has an emissivity from 0.8 to near 1.
Are you saying that I should have used wooden dowels instead? I was hoping to actually see the heat flowing between the rods, but that didn't happen.
@@ScienceAsylum Hi, all you need to do, I think, is paint or put tape on the bars so the camera's detector (microbolometer) measures/detects the heat. Buy or borrow a silver bar or coin as it has the highest thermal conduction. Cool.
Great video as always!
Thanks! Your full-size LEGO 3D prints are total bangers 👍
@@ScienceAsylum Thank you!
Very cool. My math class spent about a month on the heat equation. Good times.
It's kind of a big deal.
Why water can freeze if it sees space.
Everything is constantly radiating energy out in every direction. So why doesn’t everything constantly cool down.
The objects around an object are radiating at the same rate (if they are all the same temperature)
So set a book on a desk next to a wall. The book radiates energy toward the wall. At the same time the wall is radiating the same amount of energy back at the book. Same thing with the ceiling. The book is radiating energy toward the ceiling and the ceiling is radiating toward the book.
Now put a pan of water in the middle of your yard at night with a perfectly clear sky. The water radiates energy toward the bottom of the pan and the bottom of the pan radiates energy toward the water. Same thing with the sides of the pan.
Now the top surface of the water is radiating energy up but there is nothing above the pan of water radiating any energy back at the water.
This is why I think a pan of water on a clear night with the temperature outside at 38 degrees Fahrenheit can freeze.
Please correct anything I got wrong on this. I have seen it talked about but never seen anyone actually describe exactly why water can freeze like that.
Nice to see you're back to some physical experimentation
Yep! There should be more of that this year, now that I'm setting up a work space in my garage.
Consider.
The emissivity of the surface of a material is its effectiveness in emitting energy as thermal radiation.
Shiny objects like aluminum (low emissivity) while hot to the touch may not appear hot on an infrared camera.
The opposite of a black body.
This may explain some of the issues with your experiment.
pure silver is the best at this, he could paint his subjects next time with some black 3.0 paint
@@MrPruske an excellent solution
Love your videos and always awaiting the next upload 💓😍🤩
I love the FLIR camera! I have observed the best results by filming in the dark. When filming in infrared One must consider setting up the environment to get the best contrast. Also consider reflective surfaces etc. Infrared is still light (obviously 😅) and not as intuitive to work with. Always love your videos!
Yeah. When I was filming the doorwall shot, I noticed I was seeing the infrared reflections off the glass rather than the glass itself.
@@ScienceAsylum have you ever touched your windows on a cold winter day? I'd like to see what infrared footage you can get when its cold outside.
Didn't expect the cold humour, burst into laught. Well played Nick , well played.
The end was great. As soon as I stated the video I said in my head. Smart man makes a video which makes money also gets a thermal camera which can then be used to conduct a thermal review of the house and its all a write off for business. 😅😀😀
"I hate it when I don't understand something" I feel that, I feel that
That terrace door window demonstration reminded me of Ace Ventura, you definitely should have screamed AAAAAAAA when opening and closing the door :D
The músic at the infrared test on the Window is Amazing.
I've never thought that much about how infrared cameras and mirrors work, and is kinda mindblowing. But then this video reminds me about thermal equilibrium and Heat Death and now I'm sad again.
That equation.... I think the main struggle people have with higher mathematics (the divergence symbol, partial differential symbol that looks like an upside down lower case "e") is that we expect people to not learn how to draw these symbols until college. All other symbols for math and language are taught way earlier in life, in grade school. To suddenly start inserting new symbols and expecting people to remember them and their meaning is, I think, a big reason why so many people do not go into science and engineering.
You can see through objects that are opaque for wavelengths of visual light with IR cameras. Germanium and black barbage bags are two examples
Would be nice to see a comparison of steel and copper re heat conduction.
I have a professional thermal camera at my job, it has pretty accurate temperature measurements.
Just some facts about thermal cameras:
- shiny metal surfaces do not radiate heat in the range of the thermal camera. They act like mirrors and often 100C degrees of difference shows up as 5-10C degree. You need to apply paint or electrical tape to metal surfaces to be able to measure it.
- some opaque plastics are completely transparent in IR range
- farts do not show up on thermal camera :))
- surfaces of liquids are cooler than the liquid below, you can not trust the measurement
Good to know 👍. Thanks.
Ideas for the thermal camera: points of impacts (such as a ball bouncing) and a material's stresses (bending/deforming a material).
I liked the Ace Ventura-style sliding glass door stuff. Funny!
Something about the patterns of the ground were pretty fascinating to look at. Almost like abstract art or something.
Always love your videos! Crazy for life!
“… is governed by the heat equation”
EXAM PTSD ENGAGED
😆
I think about this sort of thing when doing woodburning art. The shape and size of the tip affects speed of diffusion.
I’ve been contemplating thermal conductivity and stuff like that because I needed a dehumidifier and there was an old abandoned water cooler at the house I moved into, so I decided to chop the top off the stainless tank inside the machine and blow air into it so that it condenses on the sides where the coils are... which works but because the coils only cover about 1/3 of the tank it doesn’t actually accumulate all that much moisture before it cycles off and defrosts into the drain at the bottom of the tank and goes into a bucket. What I need to do is fill the area outside the tank where the coils are with something thermally conductive so that more of the tank gets cold, and then of course surround that with a layer of insulation to keep condensation from building up outside the tank. I was looking into materials and it seems like mercury would be the ultimate substance to use but obviously will not be since it’s extremely unsafe, so something more inert and commonly available will have to do... I’m thinking sand, but for some reason gravel has better conduction which is a bit confusing since it wouldn’t make very good contact... also sand conducts better with moisture in it, I suppose it makes sense since more contact conduction can happen... gotta give it a try, not sure how it would handle the expansion if it froze, but I guess I’ll see if that happens.
I'd be really interested in looking at very far away objects to see how much our atmosphere interferes with radiative heat. Or, if even possible, seeing how different the moon looks in IR over the visible range.
As a certified FLIR thermography engineer, thank you for explaining this in a really simple way. There are a couple of cool experiments you can do.
You're welcome 🤓. What kinds of experiments?
Just a heads up (and I could be wrong) just like visible light in the EM spectrum is emitted by electrons vibrating at a certain frequency w/ a certain wavelength, the EM waves emitted by objects along the infrared spectrum just so happens to correspond with the vibration/“frequency” of the atoms as a whole. Which is why it works to detect temperature
Dude I will always like and share you!
After PBS, you are are the ONE channel for knowledge !!
*kiss and *thanks
Some glass *reflects* IR quite well, which I usually rediscover when trying to measure something through a window... electronics (computer circuit boards especially) are educational to look at, I've used an older phone-based thermal camera to diagnose failed chips and motors in industrial equipment.
Yeah, when I was setting up the doorwall shot, I could see my infrared reflection.
Hi Nick, use the camera to demonstrate how heat pipes work. Regards to Emm.
You should explain emissivity and why gloss and matte surfaces matter. I have burned my skin with polished alluminum because thermal camera showed 60 degr. C but it was 130 deg. C. Solution was to tape piece of paper to the gloss material and measure that to with the camera.
Yikes! When I was filming the doorwall shot, I noticed I was seeing the infrared reflections off the glass rather than the glass itself.
@@ScienceAsylum The problem with glossy surfaces is that camera measures the reflected temperatures and the surface temperature at the time. You will measure the mix of the both, depending how much is reflected to the camera. EVERY camera and even laser-pointer thermometers have setting for surface emissivity. Every time you measure something, you must first check that setting and change it according to the surface you will measure. Even with that done properly i find it better to have a masking tape with me all the time. The tape is thin and matte and it will show almost perfect mesurements.