"I'm just in a different moment" - that is gold. Consider it stolen.

@TheRealDoctorBonkus

5 жыл бұрын

Hey! I know you!

@PWARHOLM

5 жыл бұрын

My thought exactly ;-)

@Addsomehappy

5 жыл бұрын

Great, now after this vid on Tom's channel, you are everywhere!

@DomBurgess

5 жыл бұрын

There are some situations where you probably shouldn't use this phrase. eg. whilst trying to make a baby.

@MedlifeCrisis

5 жыл бұрын

@@DomBurgess Better to be in a different moment than in a different partner

That commentary on the stock footage was the best part of my day.

@nagualdesign

5 жыл бұрын

My favourite part was the pointing. "Look, a baby! Look!" 😁

@user-cn4qb7nr2m

5 жыл бұрын

Oh, cheer up! What the hell with your days?

@idontthinkso2431

5 жыл бұрын

Left hand: stay still Right hand: whooo hoo

I love this!!! My husband and I are both engineers. I think we asked more questions about the machine than the baby during ultrasounds. The tech thought we were hilarious 😋

@SteveMould

5 жыл бұрын

Brilliant!

@SomeGuy-lw2po

5 жыл бұрын

@@julialennjastorch2630 I'm a rail engineer (traction and rollingstock) we also use ultrasound on the train axles, we have to check for hair line cracks within the axle. I believe ultrasound is used for lots of testing purposes in engineering

@sarahwade197

5 жыл бұрын

@@julialennjastorch2630 , I actually wasn't familiar with that application! I know ultrasound is used in a similar way to check the structural integrity of multi-ply materials. For example, it's the only way to detect damage to the inner layers of the carbon reinforced plastics that are used in newer airplanes. I only took one class on the topic in college, so I'm not an expert on the topic. I suspect there must be a different "ultrasound gel" for every new material application.

@xDMrGarrison

5 жыл бұрын

nice :P

@RESUHT

4 жыл бұрын

Julia Storch i think the word youre looking for might be appenticeship, or possibly internship (american, but im not, so i dont know much about internships)

Such a cool demo!

@BrandonThomasRansom

5 жыл бұрын

I agree! This isn't EXACTLY analogous, but it's a great way into explaining radio frequency reflected power. Impedance matching is important in a lot of applications!

@romanieo

5 жыл бұрын

Grady, your Tuned Mass Damper, Water Hammer and Sand Castle demo deserve equal applause. Subscribed to both channels.

@MrEazyE357

5 жыл бұрын

It's Grady! Love your videos my man.

@SireSquish

4 жыл бұрын

I can't wait to see your video where you build a functional ultrasound unit from tin cans and one of those ioniser things used for misting fish tanks.

@clintonhalunajan467

4 жыл бұрын

Hay Sir Grady, can u make an episode about this too maybe your demo toy about this will be more satisfying😍

I'm guessing your wife understands how your head works, or you've been banished to the attic till the baby arrives.

@JDeWittDIY

5 жыл бұрын

I don't know...... I think he's in the attic now.

@fatsquirrel75

5 жыл бұрын

I was thinking the babies all grown up. He finally looks like he's well rested.

@ElectricBoltZZ

5 жыл бұрын

Nah mate he was banished to the Garage; Hence the Vid :P

@cyrkielnetwork

4 жыл бұрын

"That is not my wife btw... i don't have wife anymore" ;)

@noelanwilliams3375

4 жыл бұрын

definitely the attic lol

There is a saying amongst users of ultrasound that the worse the sonographer, the more gel they use. I practically drown people in it. Brilliant video, sharing with all my scanning friends.

@Ravengeno

5 жыл бұрын

How about a large amount of pressure? Felt like the doctor was trying to break through my ribcage last time I had an ultrasound. (Of course that wasn't a pregnancy related ultrasound, but still ultrasound.)

@MedlifeCrisis

5 жыл бұрын

@@Ravengeno yeah unfortunately echocardiograms and other scans over the ribs can be challenging as bone casts an acoustic shadow so you need to get in between them. Both thin and obese patients present their own problems which sometimes also require a bit of pressure. However a pregnant abdomen is all squishy tissue so rarely requires anything more than gentle pressure

@Ravengeno

5 жыл бұрын

@@MedlifeCrisis I never thought about that, that makes total sense!

@woutervanr

5 жыл бұрын

Now I want to see someone fill a pool with it or atleast a bathtub.

@seigeengine

5 жыл бұрын

@@woutervanr Looking quickly I found it for $4-5/L. A bath tub seems to be 100-200L typically if you account for a person in it, so you're talking $400-$1000 to fill a bath tub with it. Maybe can get it cheaper in larger volumes, but idk.

This is probably the best visualization of impedance missmatch I've ever seen

@userPrehistoricman

4 жыл бұрын

Yes. It's a great representation of reflections in transmission lines too.

@thePronto

4 жыл бұрын

How about the impedance mismatch between the device head and the gel? Why does that not cause a problem?

@theelmonk

Жыл бұрын

@@thePronto It's still better than the mismatch between the device head and air (there's always air even if you press it close)

..."like I do for relaxation" That right there is when I lost it *Applause* Bravo

@__Nero__

3 жыл бұрын

Same here

@denisl2760

3 жыл бұрын

Came for the education, staying for the humor. Absolutely brilliant.

2:32. Pretty sure you could have found stock footage suitable for that scene too.

@SteveMould

5 жыл бұрын

This is brilliant.

@Norsilca

3 жыл бұрын

Steve's comment section reads like a VIP list of educational KZread

@fuckyoutubengoogle2

Жыл бұрын

@@SteveMould Is the impedance frequency depended? I notice low frequencies penetrate the walls of my house while higher ones less so.

@newchannelverygood162

8 ай бұрын

​@@fuckyoutubengoogle2 It has to be frequency dependent.

That was an amazing setup and clear explanation. It must have taken ages to put nuts on every stick.

@SteveMould

5 жыл бұрын

It did! But it's ok, I have podcasts :)

@andymcl92

5 жыл бұрын

I feel like nuts played a critical role in several aspects of this video!

@pw7225

5 жыл бұрын

2 nuts for every stick ;)

@wierdalien1

5 жыл бұрын

@@SteveMould podcasts are a life saver for tedious jobs

@Thega

5 жыл бұрын

@@SteveMould I went looking for it on mathsgear to get one for myself. It looks like it took a ton of work. Did you design it yourself, or did someone else design it?

Wait, is screaming against a wall a valid method of relaxation? I mean, now I know at least what my little brother is doing all the time...

@charlierw123

5 жыл бұрын

Idk if he was joking or not about him doing it, but it is a legitimate therapeutic exercise.

@wupsje1

5 жыл бұрын

If it works that makes it valid doesn’t it?

@seigeengine

5 жыл бұрын

People believe lots of things work that don't actually.

@lionskull1

5 жыл бұрын

I assume screaming your heart out is a valid form of relaxation, it's just socially unacceptable to scream as loud as you can.

@seigeengine

5 жыл бұрын

If you believe screaming at a wall will relax you, it just might, but that has nothing to do with screaming at a wall, and everything to do with your believing it will relax you.

In a moment of contemplative silence with your wife: "Well, I just wonder that gel is purely for lubrication or wether it servers some other purpose" This guy deserves a medal hahaha

I had an ultrasound on my leg once. They always apologise for the gel or the probe being cold, but they don't say anything about how much it tickles. The person doing my scan thought she was hurting me, but I was just trying not to laugh.

@egilsandnes9637

5 жыл бұрын

I thought your comment was a joke, but then I realized it didn't say "wooden leg", just "leg.

@pilchardpliskin9381

5 жыл бұрын

Was your leg pregnant?

@allanrichardson1468

5 жыл бұрын

Pilchard Pliskin Ultrasound scans are used for lots of medical purposes: heart action, blood clots, swollen or otherwise abdominal organs, and other uses.

@Cadwaladr

5 жыл бұрын

@@pilchardpliskin9381 Sort of.

@Cadwaladr

5 жыл бұрын

@@allanrichardson1468 Yeah, I had a DVT.

This would transition very nicely into a video on the piezoelectric effect! Cool for watches, and for Ultrasound.

@ostapkurtash6359

5 жыл бұрын

Oh yeah! That I have never seen before.

"I'm just in a different moment" I can't explain how well that describes me

It's nice to actually see the reflected pulse flips upside down in the case when original wave is travelling in lighter medium, but stays upright when travelling in heavier medium!

@SergeantTubesocks

4 жыл бұрын

Yea. When you use ultrasound on two different materials, steel with cladding for example. The steel/clad interface will actually refract the angle of sound, assuming you're using angle beam. The sound can switch from a compression wave to shear wave from a change in the incident angle

Well done Steve, I'm a Biomedical Engineer, we call them crystals I mean the components which the probe made of, and each crystal actually served both purposes of producing the wave and read the reflection (like a mic and speaker in one physical unit)

@mzflighter6905

5 жыл бұрын

These are transducers

I'm a radiographer and the explanation of this was 👌👌

I audibly gasped when you added the weights - that was one of the coolest demos I’ve ever seen!!

That wave machine thing with the weights on it models electrical impedance mismatch in a transmission line as well as acoustic impedance shown here. Makes total sense but it's still really cool to see it. I doubt many people trying to explain transmission lines use this tool but they totally should!

That dolphin animation was lovely 😊

Steve, you're great at teaching, thanks

@SteveMould

5 жыл бұрын

Thank you!

If no one has said it already, I have been a Lv II industrial ultrasonic thickness testing technician for about 7 years. I'm from Louisiana, USA. The "microphone" and the "speaker" in the ultrasonic probe (it's called a probe) are called transducers. They are often made of synthetic crystals and use the piezo electric effect to transduce electricity into ultrasound and vice versa. Steve just did a video on piezo electricity too. That was a good one! I always wondered how that worked. Keep up the good work, Steve!

Dude, as an electrical engineer who struggled with RF impedance matching, this information is golden. Thank you!

I have very recently discovered you and you became my favorite science channel! Your content is so intriguing yet is presented so well and clevery simple. Thank you!💕

That wave visualization device is brilliant! Did you build it?

@SteveMould

5 жыл бұрын

Well I put it together! But I bought the kit from an educational supplies website. You can also make one with kabab skewers, jelly babies and gaffa tape!

@gery49

5 жыл бұрын

@@SteveMould I feel like it could be used to get a better intuition for how electrical impedance works but I can't quite wrap my head around it.

@gery49

5 жыл бұрын

@@SteveMould Could you please share the address of the website?

@reddymusicfreak

5 жыл бұрын

I want to know it too!

@wills7355

5 жыл бұрын

Steve Mould would less weight added as representation of the wall not have given a closer representation?

This was interesting but highlights one of the things that I don't like about science videos sometimes. You put together an extremely well articulated and perfectly illustrated explanation of *why* ultrasound gel is used but what I was hoping for from your title is to hear *how* it couples the two objects.

My first job out of college was at an ultrasound transducer company. Later I designed radios for spacecraft. Impedance matching is critical for both. Your video took me back to both experiences. Thanks - I always enjoy your videos.

Visualizing & conceiving something, is great. Visibly seeing thus perceiving it however, is exceptional. Bravo.

Demo Highlights for powerpoints (protip: .gif versions of video run smoother!) 3:27-3:38: Reflected wave 4:20-4:27: Reflect/Transmission behavior of Lo-Z to Hi-Z 4:28-4:34: Same as above, with illustrated graph 4:45-4:51: Same as 4:20-4:27 but with greater Z difference 5:58-6:06: Reflect/Transmission behavior of Hi-Z to Lo-Z 6:08-6:15: Same as above but with illustrated graph

The awesome thing about your explanation is not the explanation itself but the details of information you pass to the viewer that makes you figure out the problem yourself before you actually explain it. Haven't seen such quality in a while, thank you!

Steve, you did a great job explaining the principles that I employ every day at work as a diagnostic sonographer.

Aweeee, congrats to you and your wife!! 💕💕

Wow, this was very convenient, we just started wave mechanics today and our lecturer showed a very similar demonstration!!

@blimy5504

5 жыл бұрын

Ours too....

It is hard to get someone that is able to explain complex concepts with easy examples. You are a Genius. Thank You :)

I absolutely love the demo you made to demonstrate partial reflection/transmission of a wave. The demo is very intuitive. Thanks for making cool stuff and putting it on the internet!

Had to learn about ultrasound and how the gel works for A level physics, really interesting actually.

So can dolphins use ultrasound to see their own unborn calves or at least the calves in the womb of other dolphins?!

@CZ-dg7te

5 жыл бұрын

Probably not their own personal calves but yes of other dolphins, there are also stories of dolphins showing a great deal of interest in pregnant humans as well in those swim along excursions. However much that added interest translates to understanding is TBD www.livescience.com/38087-can-dolphins-detect-pregnant-women.html

@kalebglenn5279

5 жыл бұрын

While I am curious about this, what he said in the video makes me think no. Sea water isn't as thick as a dolphin so there would be the initial barrier between water to dolphin which would reflect the most sound back, which is how they would "see." However, I also don't think we fully know what they can "see" with their ability. Maybe if they put their head/sensor to a pregnant dolphin and started making clicks they could "see" inside each other since they would be making contact and removing as much of the initial barrier as possible. Give dolphins some ultrasound gel, see what they do :P

@rebmcr

5 жыл бұрын

It's not exactly the same, but water is a much much closer match for a mammal's body than air is.

@jordanrodrigues1279

5 жыл бұрын

@@rebmcr I remember visiting a science museum which had an ultrasound machine set up so you could look at sections through your hand. It used a pail of water, not gel, so the impedances are certainly close enough.

@allanrichardson1468

5 жыл бұрын

They can probably detect abdominal gas as well.

I'm thoroughly impressed with the creativity and professionalism you had to employ to make this video. Good job.

Hope people like this come more in this world for filling young people's curiosity about various machines.

when I talk underwater other people can barely hear me but when I tap an object inside the body of water they could hear it from far away. when I talk I make the air molecules vibrate and then theses molecules transfer their energy to the water losing a lot of energy on the process. isnt this basically the same?

@Darticus42

5 жыл бұрын

Worgos maybe they're saying "barely hear" in different contexts, I.e. can hear the sounds but can't understand the speech because we're not accustomed to identifying sounds underwater I know sound travels faster in water than in air, but I don't know what other properties of water it has that might limit hearing (pressure? Depth? Temperature?). It might be that when you observed this you were in a different position relative to the other person and so it reaches them better/worse

@XWorgosX

5 жыл бұрын

@@Darticus42 with barely hearing I meant how loud people sound under water, kzread.info/dash/bejne/nKyD3NKJesXUhKw.html (around 10:55) this video explains what I'm trying to say a much better if you have the time/ care enough, but imagine that his helium is the air in my example, and his air is the water

@klutterkicker

5 жыл бұрын

Yeah, talking underwater is basically air to water to air, not counting the losses in the biological systems. Actually, you should be able to hear much better underwater if your inner ear has been flooded, but you would have to re-learn hearing from the thicker medium.

@JNCressey

5 жыл бұрын

When I talk underwater other people hear "blub blub blub blub eeerrrrrrrrgh".

@binra3788

4 жыл бұрын

@@JNCressey You need to breathe the ultrasound gel and then talk ;-) Dolphins impart vibrations to air vesicles that can be playful or destructive. The pistol shrimp has an amazing ability to generate implosion/explosion of sonoluminescence to stun its prey.

I wonder, how do you research these things? Can you make a video where you walk us through the research part? Like behind the scenes or something? Like if you would watch it

@dextertreehorn

5 жыл бұрын

He never explains complex things you can't do research for yourself in 15 minutes even with google ....

@seigeengine

5 жыл бұрын

Nothing complex enough that you can't do research for yourself in 15 minutes with Google is going to be feasibly packed into a short video that's going to appeal to any general audience.

@Vesperon

5 жыл бұрын

But if Steve was doing it.......I would watch that!

@SteveMould

5 жыл бұрын

@@dextertreehorn damn, takes me more than 15 minutes! I must be slow :)

@julespoon2884

5 жыл бұрын

@@SteveMould In the video, you mention that the acoustic impedence would cause the reciever to detect abt 0.01%^2 of the acoustic energy given out. However, since the boundary is traversed the 2nd time in the opposite direction, wouldnt the reciever detect (0.01%)*(1-0.01%) of the acoustic energy?

Beautiful demo. In engineering terms, the "speaker" and "microphone" is called a transducer.

“Sometimes I’m accused of not being in the moment, but that’s not true, I’m just in a different moment!” That’s the most relatable thing I’ve heard so far in 2019. Awesome video.

The attic of your house looks like it's from Mirror's Edge

@c.james1

5 жыл бұрын

It is not his house, it is a separate place, a "studio" if you will, just to film videos, at least that is what I took from what he said when he first moved in to the place.

@GeneralChangOfDanang

5 жыл бұрын

Kinda disappointed that red pipe is the only climbable thing in the room.

@mrmaniac3

5 жыл бұрын

PuzzL ooh

I hear his words, but all I can think of is: How did he build that wave mechanism...

@ryanmalin

5 жыл бұрын

Telliria he bought it

This is a great explanation. While I was watching my wife have an ultrasound I was distracted by all the measurements they take by clicking points on the images, and got thinking about using machine learning to take the measurements.

Been watching you for a while now and I reckon that this channel deserves so many more subscribers! Thank you for the content and I wish you luck for the future.

0:38 That was totally me too when my wife was pregnant with our son! I still haven’t lived it down 😂

i screamed at the wall and the only it did was piss off my neighbor :(

@SupaDanteX

4 жыл бұрын

Sometimes if you cant relax, making everyone else less relaxed so you appear more relaxed by comparison, is enough.

You have amazing teaching abilities. I could just listen and watch your videos indefinitely.

I'll be trying your relaxation techniques today. Thank you.

What happens if you have a weight gradient?

@SteveMould

5 жыл бұрын

Ooh, I don't know. That's a really good question.

@H0A0B123

5 жыл бұрын

I'm not sure if you'll observe anything unusual in the 1D case, but in 2D and 3D the waves follows curved paths.

@pillarshipempireemployee0142

5 жыл бұрын

@@H0A0B123 I was thinking about the reflection, but I never thought about 3d, nice.

@rogeriocosta1035

5 жыл бұрын

That is basically what a sound horn is. It is a good topic: how the sound can be "amplified" in a horn without any source of energy?

@guilldea

5 жыл бұрын

Thats a good question, horn loudspeakers behave precisely as such systems. Speakers have a big impedance compared to that of air and thus only 10% of the watts you put into a speaker are said to be transfered to the air, most of them dissipating in the form of heat inside the coil. If you then load a speaker with a horn the sound waves outputted by the speaker enter a small throat which will have a high impedance, this throat will gradualy flare and open up as they exit the horn, gradualy lowering the impedance until it (more or less) matchess that of air. Thus by gradually changing the impedance between the two mediums you have achieved impedance matching and now the speakers will sound louder without putting more energy into the system. More on the matter if you are interested: www.grc.com/acoustics/an-introduction-to-horn-theory.pdf

the only mistake here (near the end) is that the ultrasound transducer is not transmitting or receiving to the body through air, normally there is quite a good contact/connection, the gell is needed for three things, lubrication, hygiene and to fill the possible air gaps (barriers) and make the connection more stable and removing potential resonance....

@jetison333

5 жыл бұрын

I think thats what the video is saying

@andyrharris

5 жыл бұрын

jetison333 I quite agree. I think it’s quite clear that is what the video explains.

@AlexNaanou

5 жыл бұрын

@@jetison333 almost... the emphasis is on the air gap and on the air-skin transitional losses, but there's no word about the transducer-skin contact characteristics.... Indeed this is a relatively small detail, the general physics are correct. My issue is with the simplification via dropping of relevant detail on the same level of abstraction =)

@mrmjdza

5 жыл бұрын

@@AlexNaanou @jetison333 It's a tiny omission, but it's basically the most important fact of the video... The "0.1% times 0.1%" claim is just wrong. There'd have to be an actual air gap between the transducer and your skin, i.e. not even touching you. So as long as the transducer is in contact with your skin, it'll get a semi-decent image. As Alex said, the gel helps by removing small air gaps and reducing resonance, but it DEFINITELY doesn't improve the transmission by a million fold! (as implied by "one ten-thousandth of a percent"). That's just irrefutable.

Great analogy, helps us understand why change in impedance causes reflection.

Omg that animation with the dolphin is just perfect

Nice animation! Who did it?

@SteveMould

5 жыл бұрын

Dominic Burgess. They're great right! I did the wave overlays.

@enderwiggins8248

5 жыл бұрын

They're brilliant, they remind me of the calibre you see with Ted-Ed videos or School of Life

So the people in the stock footage are just watching a gif XD

When I was working in the heavy industry we used ultra-sound to detect defects in welding. We used wallpaper past as a connection gel.

Revising for my uni waves exam tomorrow whilst watching this and it really helped visualise the idea of impedance! Great vid as always!

What happens if I slather my guitar in ultrasound gel then?

@c0rtikoZteroids1

5 жыл бұрын

You form a single acoustic entity between you and your guitar, truly becoming one with your instrument.

@keatontyo

5 жыл бұрын

@@c0rtikoZteroids1 Or you sit and write a song about how gooey and gross you feel. Either way I'm fine with. ;)

@among-us-99999

5 жыл бұрын

You could put it between the body and a microphone for..clearer sound?

2:31 omg I'm dying lol

@rockets4kids

5 жыл бұрын

1:30 had me laughing.

I watch so many great sciency creators on youtube amd you are the most interesting, eye opening and funniest of them all. Keep it up! Thanks for your videos! i always learn a lot not only about what you teach but about being curious and asking questions.

The "speakers" are called transducers. Your description is close and does a great job of describing the basics. However, the gel also provides "matching" which put simply is a specific impedance between the value in the transducer and the value in the human body. The same concept is used in RF quite frequently.

Bruhh I thought the bottle said analgel 😂😂

@jch8376

4 жыл бұрын

Thought? Or hoped?

I believe the correct word is TRANSDUCER.

these are my favorite types of videos. I may not necessarily be passionate about physics but the anecdote and interesting explanation (and amazing graphics) help me learn some random tidbit about ultrasounds. its not useless knowledge, it helps me appreciate how incredible and advanced the everyday technology we use really is.

What an amazing channel and what an amazing video. This is such a creative way to explain this concept while still being apprehensible and coherent. You have my sub! Well done!

You're portraying the problem as if the probe is made of air. I don't know what material it is, but it has most likely an acoustic impedance higher than air. So the attenuation at the interface with the human body would be a lot less, or in other words: more tha 0.057% of the energy would make it into the body. I guess the story is that the acoustic /coupling/ between probe and body is not perfect, but you don't mention that.

@revimfadli4666

5 жыл бұрын

Nah, he probably meant the probe-air-body transitions

@klaasbil8459

5 жыл бұрын

Then he should not have focused only on the acoustic impedance difference between air and body. Besides, it is not made clear that air plays a role if the probe is held against the body.

Stop applauding the carpark, screamer boy.

That's always a pleasure to watch your videos, they're really well made and every subject that you get into is something that I've never heard about before on other KZread channels and that's so great ! You deserve more subscribers ! Greetings from France 😊

Steve, this is a great explanation! I am reminded of something: The gel acts like a balun in an antenna. I.E. it connects two (or more) elements that have diferent impedances. At the end, the word you were looking for is "transducer". A speaker is a type of transducer. It can be used to change electrical signals to sound or vice versa. Similar to motors/generators, speakers are more efficient at producing sound while microphones are more efficient at receiving sound. The transducers used for ultrasound imaging are similar to a dynamo (designed to be used as a motor and as a generator) in that they are efficient at both producing sound from a signal and converting sound to a signal. The transducers used for ultrasound are resonant in the low megaherz range (≈ 1MHz- 15MHz if my memory is correct) while speakers are resonant at audible frequencies. The reason for the high frequency is to facilitate producing a high resolution image. Which brings me to the question this video left me with: I wonder if the math used to produce an ultrasound image is similar to the math used to produce a synthetic-aperature radar image? If so, I'd love to see a video on that!

You should considerate to possibility to send drones over the airport to avoid noise pollution :p

This was a short, concise, humorous. informative and thus , for me also entertaining video! Wow, that''s hitting on many levels while keeping things simple; which is what I need most. Thanks for being here/there.

I love the way you complicated things so simple to understand.

You make insanely good content Steve. I always stop what I’m doing to see your videos. Constantly thought provoking

@SteveMould

5 жыл бұрын

Thank you!

This is excellent. I am an RF technologist, and I am going to make my apprentice watch this. I demonstrate the same principle (regarding impedance mismatch) with a slinky. Nice work!

Thanks for the great video Steve, as a musician I am always fascinated by your videos that touch the topic of acoustics (and so fourth), keep up the good work!

The production quality and the explanations were great!

Really great explanation of the utility and underlying effectiveness of ultrasound gel and wonderful demonstration of the physics involved.

I work in NDT using Ultrasound and Acoustic Emission. This was a great demo. I really liked the wave generation rig you made.

Absolutely brilliant as always! I especially love your humor-laced videos; some fun in the realm of science! (still one of my faves is your eye-twitching vid, also related to your progeny!)

I wish I could like videos more than once. Every 40 seconds or so I had the urge to press the like button again.

Nice representation of the waves BTW. I like how you showed different impedances.

the best demo for sound. loved it.

Fantastic analogy of a complex physical system. Easy to understand and engaging. 👍

That Ode to the Future link is quite cool, and I was shocked to see that it was made by a life sciences company I interned for. Very neat!

Facinating stuff Steve. Love this channel 👍🏾

Great illustration! Thanks! For the record though, you called these waves “transverse,” but I think they’d actually be called “tortional.” A transverse wave would be waving the central cord up/down and/or side-to-side.

this is awesome. watched a few of your videos. love the way you deliver the fascinating scientific facts.

I’m a Sonographer and seeing videos like that drive us crazy.

We talked about acoustic impedance and ultrasound in my intro to biomedical engineering class, but I really love the visualization with the sticks on wires.

An excellent treatise on this subject. My high school physics lab had a device similar to that, except it used a change in rod length to create the echo.

The next awesome science channel I've just discovered. I love what you're doing

I once had an ultrasound scan on my left testicle. I'd found a lump and, after a visit to a GP who _squeezed it (!)_ then reckoned it was "just a cyst", it gave me a great deal of pain for about 12 months or more. Turns out it was actually a varicocele, and being able to look inside my testicle and see how the blood vessels dilated when I tensed my abdominal muscles, flushing out the "melancholic blood" as he called it, enabled me to manage the discomfort from then on. But, like Steve, even though I was primarily there to see what was what, part of me was enthralled by the technology. What a time to be alive!

I think I’ve reached a peak of cuteness in Steve Mould’s channel, (which is rare) with the dolphin’s scene.

Beautiful wave reflection demo!

I’ve only recently found your channel. I’ve been binging your videos so much and I absolutely love your humour

This is an awesome demonstration of wave impedance. It took me a lot of hard thinking to understand this concept without such a demonstration. If I had this video it would have been much easier.

Fantastic demonstration. Radio waves through a transmission line work the same way. Physics is amazing, in part because the same principles work in so many situations!