Under the right conditions, the cavitation bubbles can collapse with enough energy that visible light is emitted, a phenomenon known as sonoluminescence. My son worked on such a project as he was pursuing his physics PhD. A photo from one of his experiments used to be on the Wikipedia page on sonoluminescence, but I don’t think it’s still there. Regardless, it is very cool to see!

I don't understand how this man never runs out of video ideas, what a crazy work ethic

While I was working in kitchen design/sales about 40 years ago, we displayed a futuristic stainless steel sink which cleaned the dishes by ultrasound. One of the odd selling features was that if you were tired after a long day on your feet, it was suggested that you could sit on the kitchen worktop with your feet in the sink full of water, switch on and get your feet all tingly and fresh feeling. We didn’t sell any of the sinks! 🤪

We use an Ultrasonic Cleaner to clean Vinyl records at Wonderland Records. It's really neat that we use sound to clean physical sound mediums.

As a child, and still as an adult, I have had a love for science. This helps my children to have the same love for learning. You make great videos! Thanks

I'm a polymer and formulation chemist. You demo just gave me huge ideas for solving a number of issues!!!! Many thanks for this brilliant treatise!!!!

This actually causes a lot of drag with standard propellers. There are some fancy new props which prevent cavitation and they are 30% more fuel efficient (which is an absolutely crazy number). They still are super expensive but could revolutionize the boating industry.

I run out of interesting things to learn and look into or projects to dink around with but this guy always manages to find and create top tier videos thanks again AL!

Cavitation, like with those shrimp/crabs that shoot bubbles. I think there are Pistol Shrimp, Mantis Shrimp and another one I can't remember. (and probably others).

I wish there was some more information about safety of those devices. I don't know about those small units but industrial ones have a designated safety zone where no one should be present when the device operates. This is due to the fact that the 40+ kHz vibrations don't only affect the water in the device. They propagate into the air and then affect things outside the device as well. Like retina in your eyes, that is immersed in a fluid, so this 40+ kHz energy is doing damage to your eyes, even if though it has been greatly reduced and cannot be felt directly. I don't know it for sure but I would bet that the buzzing we hear is some harmonic of this ultrasound that falls within our hearing range, and that would imply that the ultrasound is in the air too. I wonder and love to hear if anybody noticed if/how one's pets react when an ultrasound cleaner is turned on somewhere nearby.

If I had you as a science /chemistry/ physics teacher when I was in school, I would likely have turned out to be a completely different person. That said, I wouldn’t trade anything and everything in existence for my family. SO, thank you for wrinkling my brain with every single one of these videos, I’m glad I subbed when I did! Good fortune and endless prosperity to you and your family!

You are amazing. Thank you for your work! ♥️

I can't be the only person who thought "What would happen if I put my finger in it?"

Just got recertified for soldering (IPC J-Standard) and in the J-STD-001 guidebook there is actually a rule that you cannot use ultrasonic cleaning on a CBA (Conputer board assembly) that has solder and/or components on it. This video is a fine demonstration as to why this is a rule.

One of the best of all your posts. This was new and interesting

this is a cool thing to learn and to understand what is happening. Love to know how things work :D

Cavitation is a serious problem with ship propellers. Which is why they need regular maintenance.

In nature Pistol shrimps and some mantis shrimps use cavitation bubbles to stun their prey

Not sure if ever commented on one of your videos before. This one is actually pretty good in its usefulness. Just enough depth to inspire thought without restricting it with too much specific direction.

Having briefly worked on boats and jet skis I knew about cavitation but didn't understand it's dynamics . Thank you for expanding my knowledge.

Cavitation can also happen in cars' cooling system when you modify the engine to have a higher rev limiter so the water pump spins faster than what it was rated for, thus leading to cavitation

Amazing that you just posted this, I just bought an ultrasonic cleaner a few hours ago. Love your videos man you are the bomb!

This dude does the dopest science experiments.

Thanks for the Technical explanation it was a Perfect reminder ❤

Fun fact: Dolphins could, in theory, swim much faster than they already do, but they hold back so cavitation doesn’t eat away their tails.

I will show your video to the guys working on our pumps. It's one of the best explanations I've seen.

absolutely love this channel!! great video!

That explains a lot. Thank you for sharing this.

very educational, thanks for that - I thought the cleaning just came from shaking loose the dirt as it resonates at a difference frequency to the object itself

I love the way you explain very complex things..... In an easy to understand format.

Thank you for an other great video!! I love them!

I feel like I need one of those machines and I don't know why. Awesome !

What if the ultrasonic cleaner was big enough to fit a person, would he be able to take a bath in it? 😂

Holy cow, that's so crazy! Thank you for sharing,I really enjoyed the video!

thanks for showing me yet another use for sound based superpowers.

The soda example was very good, we used these in a lab to knock foam and air bubbles out of products. Takes a fair bit of time in more viscous things but it never gets old watching all the air bubbles race to the top in thinner stuff, makes like an underwater wave as they bunch up in eachother. Super cool

i use Ultrasonic bath to clean pair of glasses when i work. super effective at removing the dirt off without damaging anything. thank you for the in depth explanation, you are an amazing teacher xoxo keep up all the great videos

We’re getting closer and closer to understanding Mega Man 2’s Bubble Man’s true devastating power

I'm a connoisseur of concise physical explanations and that's a delicious treat you made, thank you!

Your videos seem to improve in quality lately, congrats!

we use 40kw ultrasonic units to weld copper wire (wire splicing) as well as put tabs on devices. Best method. Far better than soldering or simple twisting like wire nut. The ultrasonic action cleans the oxide off the individual strands and allows pure copper fusion (mostly). Very difficult to weld tin coated copper as the tin does mix into the heat-zone in uncontrollable forms causing a flawed joint. This method often specified by military and other harsh environment equipment manufacturers. Very fast process.

Talking about cavitation without mentioning pistol shrimps should be punished by law lmao

Amazing video to show how much our intuition often underestimates simple phenomena that can cause great damage if left unrecognized or benefits if understood and applied correctly.

Extremely interesting. Physics is a fascinating subject, especially when the right person is explaining what is happening. Great little video.

I wouldn't be surprised if he said "If you don't believe how strong it is, watch what happens when I put in my finger"

He is getting closer to discover The Philosopher Stone day by day.

Another fun fact, cavitation has been a major problem specifically in diesel truck engines where the cylinder sleeves get eaten away over time and eventually leak or even explode!

Oh damn i've learned alot... i've been so curious on how does these thing work! but now i know! Nice video!

Geologists and clay mineralogists use a similar technique to disaggregate clay particles to individual clay crystals for x-ray diffraction analysis

I remember in the 90s talk about how in the future we'd all have ultrasonic washing machines and dishwashers. Still waiting for them. At least I have a small one to clean small objects.

excellent video! thanks for sharing!

You forgot to mention there's shrimp that weaponize cavitation by moving insanely fast

That foil being destroyed is crazy.

Very interesting, James, thank you!

The condensation of this much information into a 5.5 minute video is an art form.

So it’s the same phenomenon that occurs with mantis shrimp, right? Never realized there was a practical application for this; Very cool!

Great educational videos. I like your work. But there is something that is not clear to me in this particular one. I do not really see why you say that the acoustic pressure is proportional with frequency. I would say it is proportional to amplitude. In fact when you are trying to create cavitation using ultrasound it works better with lower frequencies. Indeed pressure waves causes the gas bubbles to oscillate. When these bubbles collapse, they create these shock waves, high pressures and high temperature you are mentioning. By using lower frequencies you allow the bubbles to grow bigger before they collapse and cavitation gets more violent. Another, more detailed point, is that bubbles are most of the time not vapor bubbles (it is not the water boiling) but are just bubbles from the different gases dissolved in water. This is the same as when opening a soda bottle. The pressure drops in the bottle and the dissolve CO2 forms bubbles. You actually need extremely high negative pressure to vaporize water (in the gigapascal). There is one experiment you can do: if you boil water you will get rid of the dissolved gas. Using this boiled water in your ultrasonic cleaner will not work well at all since cavitation will be very hard to initiate. Hope this clarifies things. Keep up your good work.

Awesome. I'm definitely buying one of these.

imagine this guy at a science fair, he never runs out of great ideas

Very cool! Does it hurt to put your hand in the water while it is on?

To do list: Get a stainless steel Car with a bunch of transducers at strategic points, turn it on and watch the dirt, water and mess just resonate off the body.

that's the best explanation on cavitation I've ever heard.

What's really cool is ultrasonic wire bonding used in the semiconductor (and other) industries. You vibrate a wire on a metal surface so the two metals cold weld together

So that's how ultrasonic humidifiers work. Cool.

Wow, I just tried that with kitchen aluminum foil and after just a minute it began to punch holes!

4 million subs is absolutely ridiculous. This channel is a gold mine of useful, informative science. All ages. He describes most phenomenon in a perfectly navigable way.

it's like having tiny pistol shrimps clean stuff for you.

You’ll also be getting Sonoluminescence in the bubbles, and that’s where the heat from the collapsing bubbles come from. It’s hard to see on that small of a scale because you aren’t holding the bubbles in place with the pressure waves, and they constantly disperse. Technically, cleaning with micro fusion heat.

On Star Trek, the crew 'wash' each day using a sonic shower. No water, just ultra sound

Awesome, there must be so many uses for sound waves!

Thank you, now I understand the connection between low pressure on the rear side of s propeller, vapour pressure, cavitation bubbles and attacking metal! 😃👍

Try vacuum oil to get a much lower vapor pressure maybe the cavitation bubbles can achieve more energy

You can synthesize nanomaterials using ultrasonicator. We call it Sonochemical synthesis and it's principle is based on the cavitation bubbles. Edit: We use another type which has horn or probe. Nice video 👍

My favorite channel Thank you for your work

I use ultrasonic cleaners quite often where I work. But the water is pretty dirty so I don't get to see thing melt off like this. Very cool

ok but what would happen if i put my hand in it?

I wish you would have explained why the foil dissolves but the bolt does not. With enough time, would the bolt dissolve too? Also, when the foil completely dissolves is there sediment at the bottom of the water or is it just suspended in the water?

some restoration videos have these things they are so cool

@The Action Lab good information

Can microphones even hear/record ultrasonic waves? (I know you couldn't hear it and your speakers probably can't play it)... but can microphones record it (so it could be seen in software)?

What does it feel like on your finger? Painful or tickly?

👌 Nice video The Action lab!!.👌👌👌🙏 Thanks to send the video. I have a nice idea now ....💡👌

Engines with wet cylinder liners can suffer acutely from cavitation errosion as you described. Caterpillar engines had that problem about 40+ years ago. The solution was to use a good quality corrosion inhibitor in the coolant. The cavitation created a porous liner in the lower half of the cylinder sleeve. It just looked like a brown stain from the inside of the liner. Our organisation fitted Fleetgaurd water filters which doses the water with inhibitor plus removed rust and sand particles from the water. This is important as many engines still had casting sand left from the block casting process.

I suspect if you tune the frequency emitted to an object’s resonance frequency I suspect this would be more efficient and powerful like what opera singers can do to crystal glasses, love this though, shows what frequency can do when thought about deeply and outside the box

Can this happen in air? Can this happen in plasma and explain the Hutchinson Effect?

Hi actionlab, your video reminds me about a seemingly mad not recognized scientist (likely without a title or formal education). I used to have the links to his videos - where he - almost bored - presented his findings, that a mix of ultrasound (not 42 kHz, but he mentioned 43 kHz) and magnetic waves - did not dissolve metal - but - made it bent, cringe, split - in ways which I found quite natural to look at - yet challenging for me to get a grasp on. He for instance split a solid metal block (appearing some 10 x 10 x 20 centimeter) of aluminium, into cringing, bending, stalagmites - which were rectangular, and pencil sized. It was not looking "Beautiful" or "symmetric" or like that- but it appeared as if these maybe 100-200 pencil-sized stalagmites were evenly formed. I explained his experiments by imagining that some resonance occurred. The pencil-shaped pegs/stalagmites bent a little bit - also still not homogenously - but bent, like you would expect a tree or a straw to bend for the wind. Not a lot - but enough to create curiosity. Do you have any knowledge about this? It is like - there used to be some 6, 7 or so videos. The man looked mad. But he was certainly not mad. He was visibly bored with his findings. He set up his demonstration - for the camera - as if he actually had other more important things to do - but - that he kind of had to do this boring thing here. I have not been able to find his videos since around 2016-2017 - I have looked and searched - without success. Have you ver come across them? Well. Thanks for your great channel, which I follow in many ways - like here - and in shorts.

I ve always liked this channel but this episode was crazy cool

Would cavitation affect aircraft propellers much like the boat propellers given water and air are both fluids?

The Amplitude of the Ultra Sonic cleaner is what causes the cleaning action. It's Amplitude creates the strong pulsating Pressure on the liquid that removes the dirt on the object. And the Ultrasonic frequency (above human hearing) is Resonant to the molecules of the object to be cleaned.

The mantis shrimp can also punch so fast that it leaves a cavitation bubble to collapse with a temperature hotter than the surface of the sun

My mechanic friend recently made a video about this phenomenon destroying the cylinder sleeves in diesel engines. The vibrations from one cylinder travel through the coolant to the next, causing erosion.

What happens when you pour petrol on thermocol ?

Cool!

Cavitation is also a big problem on military submarines. Boats that were designed for stealth operations aren't too stealthy when the prop is making hundreds of sonic booms per second. In fact the design of submarines' props (and other Naval ship propellers) are classified because of all of the R&D that went into propellers that could spin faster without cavitation.

This is so cool!

This is part of why I'm very apprehensive about putting firearm parts, and internals in the ultrasonic cleaner, at some point you start to wear the finish, and enough metal that the pieces can become weaker, also microfractures can expand in hardened parts.

I love these videos! I want one of these cleaners! Do they make them big enough to put my whole house in?

Great video!

1:55 Frequency means waves would be shown closer together, not taller

But what happens if you put your hand in it, or more appropriately, a hotdog?