World Record Chain Fountain? The Mould Effect Explained

[@SteveMould]

You can also discuss this video over on reddit: stvmld.com/_sv6ydpm but there's a lot of good discussion happening here too! Really happy to finally see Mehdi's excellent video. I want to talk about one of the main points from it that people are discussing in the comments. The horizontal experiment with the spaced out rows of chain (time code: kzbin.info/www/bejne/nqmVfXinibaHaqc) I don't believe it actually demonstrates the chain fountain. The arc never gets "higher" than where it started (I put "higher" in speech marks because the experiment is horizontal, but you know what I mean - "higher" means "to the right" in the case of your experiment). Yes, the loop gets longer when measured from the top of the pile (because the top of the pile moves to the left, but that's just how chains behave, once you're in steady state the chain will just flow through whatever shape it has. The fact that the peak of the loop actually moves "down" (to the left) in Mehdi's experiment is probably due to friction and due to the fact that it didn't start in steady state. The same is true for the experiment he does off the whiteboard (kzbin.info/www/bejne/nqmVfXinibaHaqc). He lifts it up before pulling it down. It's already up to speed by the time he lets go and so almost steady state - the chain then just flows through the loop he gave it. It doesn't rise any higher than that. I would be convinced that I was wrong if someone could show, with the spaced out beads, the fountain rising after they let go.

[@ElectroBOOM]

Hey Steve! Thanks for the awesome video. It does make me question my thoughts and try to find better answers. I still haven't received the 10,000 cents in my account! :D You say "the chain will just flow through whatever shape it has" like it is much different than the Mould effect. But the Mould effect is just that, conservation of momentum and that's why the chain tends not to change shape. In my 2D test the fact that the loop is getting larger should be proof enough, and perhaps I could convince you the chain would rise "higher" if I could run faster! In my test friction is always against the motion of the chain in any direction. And I'm pretty sure my last white board test would start to rise on its own too if I had a much longer chain and higher drop AND a way to make sure those pesky strings don't tangle! Even in my 2D tests the chain lifted itself off the ground if you look closely. Eh... maybe we should revisit this with a bunch of new tests!!

[@SteveMould]

Interesting! Maybe we're arguing over semantics. When I say "chain fountain" (or if I'm feeling smug "mould effect"), I'm talking about the chain rising higher than it started. I'm pretty sure no matter how fast you ran on the horizontal experiment, that would never happen. Likewise with the spaced beads off the whiteboard.

[@johnchessant3012]

@@SteveMould Hi

[@ElectroBOOM]

@@SteveMould eh... maybe there are a bunch of other tests in order!! Future content!

[@SteveMould]

@@ElectroBOOM Yeah, more tests! I'm planning a follow-up anyway from a higher ledge. Not for science, just for the fun of setting a record. But of course I would include some robust rebuttals to your video. Just can't think what to spend the prize money on.

[@johnsherby9130]

This is the first time in my life I’ve ever gotten to see a science discussion unfold in real time. Everything else I’ve ever learned about has some sort of science dude that figured it out in the 1800s

[@niemand262]

Look up Lex Fridman. His podcasts are the most charming, accessible, bleeding edge tech and science content in the world.

[@RayRae559]

Then you must be stuck in a bubble kuz this happens all the time! Have you never seen Mythbusters?

[@tristanridley1601]

@@RayRae559 Mythbusters' science is questionable at best. But there are plenty of science youtubers covering and being a part of new science.

[@dylanmccallister1888]

@@RayRae559 this is not the same. This is an unexplained undocumented phenomenon in the 21st century and it concerns newtonian physics. 2 industrial revolutions and nobody bothered explaining why chains do that when they fall off ledges.

[@kylearmenta7138]

First time? Not even during the pandemic? No?

[@ElectroBOOM]

Hay Steve! I collected a bunch of clues from your video to keep the argument going! Here they are: - Your long chain breaks, why? Because the tension between gravity and the opposing forces caused by momentum (ones IMO help the chain rise) get too strong. The chain is still speeding up, so those opposing forces are still getting stronger but chain can't take it any more! - 2:57: Look closely at the chains, the stationary ones around that time are floating in the air before starting to go up in the loop! They don't press against any surface to start rising. - 9:18: I still don't understand why you say regular link chain wouldn't rise. They make even better levers, so the reason they don't rise is just friction/tangling IMO. Otherwise they should rise like Cambridge's spaghetti chain test. - 10:42: Can you say for certain the speed itself is not a factor of curvature radius?? It might not be, don't know. But assuming tension is not a factor of radius sounds like an assumption. - Somebody has to double check those math and equations!! - 13:38: in the first experiment the entire energy of the bullet lifts the wood only upwards (almost), and in the second one, it lifts the wood up AND it gives the wood a strong rotational energy, and yet in the second experiment the wood goes even higher?? FREE ENERGY?!! I think the test might be an anomaly and must be repeated multiple times for definite average results. Or maybe he did, I need to see his video. - 15:59: The chains push against each other due to Mould effect!! You are pulling the chain away from the pile and they pull back (you see them actually curve back 16:16 forward). You should space them like me so they don't bang against each other and they still rise if you try to make the Mould effect like I did, pulling past the pile. But basically, waves traveling through the chain causes them to bang against each other and pushes the bundle around. I'm not convinced that's an indication of lever effect. - 18:32: Those arbitrary shapes in the chain are "waves" of energy traveling through the chain, that happen to have the same but opposite speed as the chain traveling and so they seem stationary in location. I'm sure their speed being opposite the chain speed is not a coincidence. Those waves IMO are created due to how the chain links are piled on top of each other and how they unwind. So, those waves already have energy that seems to be resonating with the chain somehow and so their energy doesn't die away. So I think if this is done in space station from stationary with arbitrary shapes, you would just pull them flat for the most part and create multiple localized Mould effects. Send the 10,000 cents to my paypal. Thanks!

[@SteveMould]

- Yeah, the tension is related to the velocity so the faster it goes the higher the tension - 2:57: To my eyes it looks like the floating ones are floating because of the cross pulling effect I describe later in the video. So they're still getting an extra kick up. - 9:18: Good point! - 10:42: I'd love someone to check! - 13:38: I don't believe we need to fix any free energy problem. Like with the chain fountain, I suspect this bullet experiment falls into the category of problems where half the energy is lost to heat, and some of that is recovered by the kickback. - 15:59: Interesting! In the slow mo replay it looks pretty clear to me that there's a lever effect. There's a point I want to make about your experiment with the spaced out chains. I'll probably put this as a pinned comment too as it seems to be the main thing people are commenting on: I don't believe you demonstrate the chain fountain here. The arc never gets "higher" than where it started (I put "higher" in speech marks because the experiment is horizontal, but you know what I mean - "higher" means "to the right" in the case of your experiment). Yes, the loop gets longer when measured from the top of the pile (because the top of the pile moves to the left, but that's just how chains behave, once you're in steady state the chain will just flow through whatever shape it has. The fact that the peak of the loop actually moves "down" (to the left) in your experiment is probably due to friction and due to the fact that you don't start in steady state. The same is true for the experiment you do off the whiteboard. You lift it up before pulling it down. It's already up to speed by the time you let go and so almost steady state - the chain then just flows through the loop you gave it. It doesn't rise any higher than that. I would be convinced that I was wrong if you could show, with spaced out beads, the fountain rising after you let go. - 18:32: Yes! My understanding is that it's no coincidence that the wave speed matches the chain speed. It falls out of the mathematics. The speed of a wave in a chain is √(T/λ) and in the Biggins and Warner paper they figure that T = λV², so they match. So yeah, that could explain that.

[@ElectroBOOM]

@@SteveMould Thanks for the replies! I have one more point to add: - If Mould Effect truly acted like a fountain, with table pushing up while gravity pulling down, wouldn't the chain act more like a water fountain, as in the chain above the table surface (already slowed down by gravity) would collapse over the chain just pushed by the table due to gravity? But we see the chain is always stretched and under tension. That indicates the chain is pulling back keeping itself under tension, which would agree more with my conservation of momentum theory.

[@zyansheep]

Yoo awesome videos guys :)

[@mathewzacharias7233]

@@ElectroBOOM hi

[@creatorsassets]

How much time did it took to write this??

[@MedlifeCrisis]

I love everything about this. The collab, the disagreement, the lengths you went to, the worldwide legacy. This is KZbin box office for nerds like me. I'll miss being your neighbour Steve! Amazing stuff.

[@LeoStaley]

What? My two favorite KZbinrs used to be neighbors? This only raises the question of why you didn't do more collabs with Matt Parker. And no other questions.

[@ezramantini8078]

You said it man

[@dextrodemon]

i thought you two were related tbh

[@dwmueller76]

LMAO! I was absolutely cracking up at “I’m not saying I’m better than Einstein! It’s just”! And “ wait your last name is Mould? As in the Mould effect! Love it!

[@LeoStaley]

@@dextrodemon Medhi is Persian, rohin is Indian.

[@1whoDoesSimply]

Finally a video that doesnt cut at the first experiment so that we can actually see it. You're one of the best science channels ive ever seen. The opposite of clickbait - in the best way possible. :)

[@MIOutdoors1]

I absolutely love his reaction when the "Mould Effect" is coined. No false modesty here, just a genuine fantastic response.

[@engi9715]

If they ever teach the mould effect in schools, we'll have a great story to tell our kids

[@llyn5759]

I feel like that was peak British "hum[our]ility" lol

[@aceman0000099]

​@@engi9715 the story would go like this "ah yeah I was subscribed to the guy that discovered it, not when he posted the first video or anything but years later when he made a follow up. " And your kid would say "okay"

[@zUltra3D]

​​​@@engi9715 imagine if his kids learn about the mould effect or someone's telling them about it, they'd be like "yeah, my dad made this"

[@DavidVerch]

When I was in the US Navy we visited Cyprus and when we tied up to the pier they brought an anchor on a barge. We were tied to the pier on one side and the anchor on the other. When they let go of the anchor on the barge the chain made the fountain effect. It was amazing to see.

[@dawnhansen7886]

WOW ❗ Would like to see this on a video

[@williamhuddleston8927]

I’d bet it was! Especially with those huge barge chains. I’d be a bit scared to see something move with that much energy lol

[@jkvintageanalog8489]

the only thing is the chain never hits this maximum curvature. The chain laying flat on the table is not what is going on in the container and this works without a container. If the tensions effect was the only effect why does it come up in s curves wouldn't this effect be totally linear. Wouldn't it force the chain to rise straight up and straight down. the chain rises up at very low angles this certainly this is very odd. If it needs the container then why for most of the fountain is it not touching the container. At very least that proves the container is not required for the effect maybe it helps by forcing it to start at a higher arch but certainly not needed i just dont buy it.

[@salt-emoji]

Very cool but also, absolutely terrified of that.... isnt a single link of navy anchor chain like a couple /hundred/ pounds? Also that raises some very perplexing issues about the effect that deal with mass...

[@g.d.1215]

@@jkvintageanalog8489 container is required

[@cogspace]

"It's no big deal. It's just a three-story high sculpture in Guatemala" is the best humblebrag I've seen yet.

[@Geckuno]

Its brag. Impressive of course.

[@sashalo1194]

“Humble”

[@MiceAndMinecraft]

I remember in the 1990s helping my parents put up Christmas decorations one year and we had these plastic tubes full of multicoloured chain beads, and we discovered the chain effect by accident. Dad could it especially fascinating and was showing everyone over and over.

[@TransoceanicOutreach]

I remember exactly the same thing, but in the 60's. We called it the angel fountain.

[@echonox31]

That's such a dad thing to do

[@ElectroBOOM]

Yeah... now watching this I'm even more confused... :D I think we DO need someone smarter like Neil deGrasse Tyson or some mechanical genius to review and comment. But then again as an electrical engineer, I am over qualified for this!

[@FrankDrebin]

Or maybe some rocket engineer? cough SmarterEveryDay cough

[@DrGibarian]

Maybe Bill Nye?

[@GMC997]

@@FrankDrebin Well, he does some "similar" reasearch on the "whip effect"

[@quertz42]

I think you both might be right, but be describing slightly different effects: In Mehdi's video, the chain doesn't raise: The top of the turning point stays the same position during the tests. Only with the additional kick-up force can the top of the chain actually raise further while the chain is falling

Score so far Mehdi - 1 Mould - 0

[@twojuiceman]

The Mould effect, a Parker square, and Grimes dice all walk into a bar. The bartender says "Am I in a numberphile video?"

[@mjolnir3309]

Underrated comment.

[@maruftim]

lmaooooo

[@otakuribo]

In walks Medhi's constant

[@Evandroworks]

Has Parker ever followed through on his experiments on when and why coins fall on their sides? I remember he asking people to buy plastic coins, test, and submit the results but never saw the results?

[@TimeBucks]

the most ambitious crossover event

[@Dogo-cp9vx]

Yes

[@The_Juggalo_Joker]

TimeBucks: "the most ambitious crossover event" Avengers Endgame: "am I a joke to you?"

[@morellatovar4151]

Bien

[@morellatovar4151]

Bien

[@bjarneschroder591]

What would happen if you drop the glass with the chain in it or lift it up while the chain does the Mould Effect? Would the arc move with the glass or would it stay in place?

[@lizardi1037]

Great question

[@hughjass1976]

Theoretically, bit of both. The upward force of the rotation would have reduced effect, as more of the downward force is absorbed by the fact the chain is already falling. So, if I'm correct, the chain would descend with the pot, but at a slower rate than the pot itself

[@drawapretzel6003]

No, you see the mould effect with every kind of chain, the variable is how high it goes and how much force it has. This is clearly an artefact of the tensile force being distributed along the length of the chain, the same thing that causes chain to accelerate faster than gravity. Mehdi's mechanical analysis is spot on.

[@marcus3d]

Exactly. When you understand why the chain accelerates faster than g then you understand where the hump comes from, and why Mehdi is correct.

[@mr.cooper2031]

I concur. I did very much enjoy watching both sides of the wager. It definitely adds a little flavor to the debate.

[@thezeus6831]

chain dropping faster than gravity? you mean chain falling faster than something of equal mass? because that'd be due to air resistance...

[@drawapretzel6003]

@@thezeus6831 someone, I think it was Mehdi, briefly mentions the fact that be cause the chain is in tension, it continuously accelerates until it reaches equilibrium with the upwards force to pull the rest of the chain after it. A single object accelerates at g, but this is a weird object, in that it continues to accelerate until the bottom hits the floor, then it maintains a speed of equilibrium. Think of it this way, the first link on the chain gets a little extra time to accelerate before the second link, but they're attached, meaning the second link gets a g acceleration in addition to that little bit from the first link pulling on it, meaning by the end of a long chain, the whole thing is actually accelerating down faster than an object normally falls, aka faster than g. You could do it in a vacuum, it would still do it, it's because gravity is pulling on the entire chain, and the chain is also pulling on the chain. They combine additively, as it were. If you bunched the entire chain up and dropped it all at once it would just fall like anything else, but because of the mechanics when it's falling down in a straight line (especially with a little boost from the guy throwing it) it's neither a solid body nor in free fall, it's accelerating.

[@Raykkie]

​@@thezeus6831 Your comment made me realize that Veritasium's video about the phenomena is 10 years old now. Oh lord. (Mass doesn't matter when it comes to gravitational acceleration btw)

[@BallisticBen247]

Everyone being amazed by the mould effect and I'm laying here thinking, "Holy Sh*t. His microwave is right beside his recliner. This man IS a genius!"

[@Zarytex]

what bothered me most is that he put on the gloves wrong on the crane at 5:29, looks oddly funny :D

[@tteot1wph]

@@Zarytex lol maybe he’s worried about scratching the back of his hand

[@DarthTwilight]

Truth

[@juneguts]

@@Zarytex what on earth do you mean

[@Zarytex]

@@juneguts the right glove on the left hand and left glove on right hand, the black side is the grippy one thats supposed to be the inner side of your hand when closed...

[@AtomicShrimp]

The chain inside the beaker is all coiled/piled up, however, outside of the beaker, it is falling comparatively straight, so for every X length of chain falling outside of the beaker, the uptake distance inside the beaker is much shorter for the same length of chain to be paid out - the vertical component of the distances travelled by the chain on the falling side vs inside the beaker (relative to the actual length of chain) are not equal.

[@AtomicShrimp]

Or in other words, any given length of chain requires less force to pull it up out of the beaker, from a coiled position, than the force being generated by the equivalent length of chain on its way straight down, outside of the beaker

[@kennethnielsen935]

Bump

[@AtomicShrimp]

Been thinking about this overnight and I think my above explanation is incomplete - after all, there are a great many more balls falling outside of the beaker than rising inside it. I think this is part of the picture, but not all.

[@bowenhunter2558]

Holy shit its atomic shrimp, and here he is, making his rather intelligent remarks as usual

[@_mossy_8520]

I guess there isnt anything atomic shrimp can do

[@MartinInBC]

I'd have given good odds that when something called "the Mould Effect" was discovered it would have come from a student's share accommodation.

[@aceman0000099]

Many of my flatmates turned out to be aspiring amateur mycologists and enjoyed leaving fruit uneaten for months without cleaning it

[@mattjohnston2]

I'll be honest, Mehdi's explanation seems to make more sense to me. I _love_ the discourse here!

[@MrMasters1983]

microcosm of the state of the world. Intellectual proven wrong and then doubles down and decides to market his error with gaslighting.

[@thijsdekabouter9198]

Yup mehdi is right

[@megan00b8]

9:18 you can actually see the mould effect on normal chains in the video, but it's much lesser and barely gets off the edge of the beaker.

[@ncitshubham]

Exactly my observation. Steve said, "the effect doesn't work on normal chains." But it does seem to work in own videos, albeit to much lesser extent.

[@blahorgaslisk7763]

@@ncitshubham And the lesser effect can be explained by the added resistance in the coiled chain. Contrary to the ball chain the link in a normal chain can interlock and easily catch on each other. To pull the chain from that mess requires a lot more energy than uncoiling the ball chain. It would be interesting to see this tested with say steel wire rope or different kinds of rope. I have a feeling these would perform much like the ball link chain. I think I've seen this happen with high strength Aramid core rope, but it was a long time ago so I can't be sure. Now that kind of rope shares some properties with the ball link chain, such as having a minimum bend radius that's pretty large. Same thing with wire rope, it doesn't like to be bent really tight. There's also chains that has a center piece that divides the link into two parts. Using that should cut down on how much the resting chain can entangle, but it might also increase the friction in the links making it run out slower. Testing would be required there. Also those tends to be the heavier chains and will weigh a lot for any significant length as well as being very expensive.

[@Audio_Simon]

Yep

[@fxm5715]

Mehdi's 2D floor experiment seems a pretty powerful argument. He gets the effect with multiple kinds of chain on the floor, with the rows of stacked chain not even touching each other. Steve's version where each layer is touching does show a transient downward force, but Mehdi shows that it is not a significant contributing factor.

[@mr.alkenly889]

you can actually see that there isn't a downward force that launches the chain, the chain gets slightly launched away from the pile then forced back into the pile.

[@cate01a]

not so sure! with medhis ground experiments, are we sure the peak is rising? isn't the idea that the mould fountain, is when the peak rises? could the peak we see with medhis experiments just be from a chain retaining its pattern, as is usual?

[@chrishatch1008]

​ @bob bob I feel the same. In Medhi's floor experiments to show the Mould Effect the peak of the chain would need to stay in the same place or move away from the direction of the pull. However, the peak clearly moves in the direction of the pull, i.e. the peak gets lower and lower.

[@iain_nakada]

@@cate01a Agreed. Apart from the physical situation on a floor being quite different from the chain falling against gravity, I don't think any of those examples show a rising loop. Even the fishing twine off the balcony at the end fails to maintain the rising loop, it steadily shrinks.

[@stevy2]

Watch Steve raise the beaker as the loop of the chain rises into the air. kzbin.info/www/bejne/nqmVfXinibaHaqc why?

[@ruebancastro3189]

Your tenacity is overwhelming and profound Steve Mould.

[@rushabh_b]

For a case. Try dropping the beaker/container after 'starting' the chain. It will help us know if you're correct (kick back effect) or Mehdi (momentum)

[@stephensmith799]

Great idea👍👍👍

[@leandrorodriguesdefreitas3856]

Or experimenting different downward velocities until you cancel out the kickback effect

[@danielmaylett1710]

All scientific discoveries start with: "huh...thats odd"

[@c.jishnu378]

2 years, 366 likes and no replies? Let me change that. (Today is 23 May 2024).

[@c.jishnu378]

2 years, 366 likes and no replies? Let me change that.

[@MttGaming904]

"Huh... your profile is odd."

[@kelansteel5322]

After watching Mehdi’s video and his slow-mo 2D demo, it seems that looking into the behaviour of a whip could prove useful into figuring out the fountain effect.

[@tambow44]

The Mould Effect *

[@DavidGossettMusic]

Yeah, Mehdi's video has me more convinced than the "lever" hypothesis. The other chains hitting the lip of the beaker definitely saps some energy from the effect. So possibly the best way to test it is to eliminate the beaker and use some other way of dropping them.

[@stickiedmin6508]

I think you're on to something - when you crack a whip, you jerk your arm and the wave travels along the length of the cord. What if, instead of just quickly jerking your arm and then stopping the movement, you could keep applying that force, steadily increasing it at something like 9.8m/s2? I think that's what's happening - dropping the chain at the beginning is like the arm jerk that makes a whip crack, but instead of being a transient force, it keeps increasing (due to gravity) which makes the wave amplitude increase as it 'travels' (in this case, the wave doesn't travel along the chain, so much as the wave stays where it is, and the chain moves through it) along the length of the chain / whip.

[@demianpomeroy4000]

Moment of enertia, like cracking a whip or a figure skater pulling their arms in to spin faster, the chains moment of enertia decreases at the point it changes direction, this means the angular velocity must increase, then having the ability to pull the weight of the chain up and out of glass

[@daydream605]

Ah, i just typed this without reading comments first. Gg

[@budsak7771]

I remember playing with these chains as a kid and the one thing that would always keep me coming back to them was the way they kind of "lock up" in a way that would stiffen them up. I can't remember exactly what it was I'd do but it, honestly, was the only thing that kept me playing with them. 😃

[@466rudy6]

Yes it only works with bead chain because it can both pull and push, unlike regular link chain.

[@barabbasrosebud9282]

Yes, it’s that metal bead chains stiffen under tension which obviously explains the idiotic “Mould” effect.

[@RealTheScienceCat]

@@barabbasrosebud9282 y u a jerk?

[@ZeketheZealot]

I wonder what would happen if you dropped the “pot” whilst the chain fountain was about half complete? Would the chain continue fountaining even as the body of the chain at-rest falls? Would it all fall together at once, ending the fountain effect?

[@SapphireTvYt]

I did not test anything but I think for sometime due to inertia it will act like fountain,but eventually other side will also pull it down.

[@wangchi623]

This is actually a fantastic idea to drop the "pot" while the fountain is happening. Maybe it would give some insight into the forces at play and how they're being generated.

[@TLJ1025]

No, because it would fall faster than the beads are coming out, so it would essentially just yank the fountain down. At least, that's what makes sense in my head. Lol didn't test it.

[@lofturhjalmarsson9896]

and try moving the pot up while mid experiment , at different speeds

[@sharpnova2]

the chain would turn into buttered toast and the pot , a cat.

[@tmaka2354]

Even when you play the video of chains not working, it literally shows that it’s working. It just doesn’t have as much of an effect due to friction

[@cadenmcqueen4615]

so true bestie

[@raunefare]

Electraboom wins in my book. When he shows them laying flat on the floor space out there no argument.. no lever effect.

[@crispykitten]

Amazing I posted the same before scrolling down. I saw the same thing. It also fits with ElectroBooms take on questionable pots for the Cambridge examples.

[@Ferro3D]

Also the weight of the chain, what we're effectively seeing with the effect is a wave and a heavier chain will need more energy to overcome inertia and gravity that can't go into sustaining the height of the wave meaning the walls of the beaker were just a bit too tall for the night the chain was being dropped from. What's kinda funny is that if he had gone just a bit higher it probably would have easily been enough to clear the beaker.

[@iain_nakada]

@@Ferro3D I'm not sure the weight of the chain will have a huge effect. Acceleration is constant regardless (g), and the heavier links falling will pull on the heavier links in the beaker, with equivalent mass. The shape of the links and how they're connected seems to be the critical factor.

[@Fade2GrayOG]

I think Mehdi has this one. His "2D" experiments were pretty convincing.

[@RubixB0y]

Yeah, 2D fishing weights were pretty conclusive for me, no backwards lever effect to rely on

[@johnmcauliffe8824]

@@RubixB0y yeah, even the Cambridge people said that it wouldn't happen with that setup, yet Mehdi proved it did.

[@DickShooter]

Yes, absolutely.

[@bobbym6130]

They were, but did the hump get bigger over time or stay constant?

[@Technichian462]

I think Mehdi's 2D experiment shows something. The 'hump' curve stays constant without the chain having gravity pulling it. So the reason for the rise is obvious. Its simply gravity pulling it faster. The hump increases in size because inertia keeps the curve of the hump constant, so the inertia needs to go somewhere, and that seems to be up. The chain in the container has zero relative motion, and the faster the chain gets pulled, the more inertia it gets, and that inertia resists change in the hump, which creates torque, which pushes the chain higher. So gravity and inertia and torque?

[@HellOnWheel]

I've been doing this demonstration with the STEM edutainment org I work for for several years (we use the Steve Spangler one) and I think I even knew it was called the Mould effect, but never knew it was named for you or that you discovered it! When I first saw the title of this video, I thought, "well that's funny, he has the same name as the effect". 🤔🤦‍♂️

[@epaybe]

Steve: "Even Einstien didn't have an effect named after him." Einstein-de Haas effect: Am I a joke to you?

[@parkinfurkmaz2877]

Also Bose-Einstein condensate (effect)

[@Hanesen5]

And the element Einsteinium 🤔

[@MrNicePotato]

People could have named the photoelectric effect after him, but they didn't eh?

[@eyallev]

@Adrian Martinez Dorsett Einstein has a bridge named after him

[@eyallev]

@Adrian Martinez Dorsett see? sure, it's another "half", but it's a whole bunch of halvs, so there.

[@PretzelBS]

He’s so proud that he’s got an effect named after him

[@hogejo]

I would be even prouder. Would have microphones with me to drop any time needed.

[@shubhammaurya3671]

Why not, even Einstein does not hold this glory

[@LordSchnoz]

Gonna be a little awkward if Mehdi is right, which I think he is, lol.

[@otakuribo]

I really hope these wholesome scientific disagreements start trending on KZbin and elsewhere.

[@feedbackzaloop]

Too bad those are still regular disagreements, just upon scientific matter. The whole argument is based on the series of "yeah, but" rather than scientific methods. Showing an eqeation is not such. Numerical verification of the equation with statistical analysis of experiments is

[@kr1ng_w]

*less than 6 hours later its now #44 on trending* xD

[@DanSchaumann]

@@kr1ng_w #30 on trending fifteen minutes after your comment!

[@aufornvic]

This is fantastic Steve. It can't be any unknown force from the pot. When the momentum begins the chain is being forced to turn 180 degrees, which creates centriugal force, which lifts the chain out of the pot. I think it's pretty simple. Better to be known for the 'Mould effect' than the 'Osbourne effect'. Look it up, it's a marketing thing.

[@mfbfreak]

I agree with this. If the chain rotates 360 degrees the loop of chain will stay in place, because the forces it experiences should be equal in all directions. Now remove the bottom half of all force vectors, and because all force is directed upwards, the loop wil climb upwards until it's equally large as the force of the length of chain pulling down.

[@brunnomenxa]

Some of this movement can occur because all of the current is coiled. I imagine how the behavior would happen if the chain was never coiled at the beginning of the effect.

[@af9287]

@@brunnomenxa Agreed. The chain has some twists in it when it's dropped into the beaker, but the twist can't escape because the ends of the chain aren't free to rotate (one trapped under all the other chain at the bottom of the beaker, the other on the ground), but it does try to even the twist out over the length of chain that is free to move. As a result, as the twist in the chain uncoils, the stiffness in the connection between the beads causes some weird movement. Because the beads were on string (instead of stiffer metal connectors), they don't fountain, since the string can bend and uncoil in ways that don't fight gravity.

[@alext-f5255]

No, he specifically demonstrates mathematically that the centrifugal force results in an arbitrarily tight angle.. hence why this effect is not observed in regular chain.

[@nw4042]

​@@af9287Only problem with this theory is that all elements in steel chain are free to rotate along the chain axis. Each little ball and rod is it's own little free wheel along the chain axis. Ergo, you could (strictly hypothetically) "twist" the chain infinitely and you will have stored zero torsional energy. Go grab one and test it yourself!

[@persinitrix]

This is exactly what KZbin is supposed to be about. Making me care about something that i had no interest in initially and making me smarter for it

[@borninator]

Watched both and I'm leaning a bit more towards Mehdi's explanation. Intuitively it just seems that the pushback force isn't strong enough to account for that massive height. The truth is probably some blend of theories here.

[@dougc78]

The pushback force is cumulative

[@tscook10]

@@dougc78 It can't be cumulative, each link in the chain has to be accelerated to the chain velocity.

[@kabsantoor3251]

The push back force increases with the speed of the chain since greater speed of the chain means the tension at the end of that "rigid three bead part " of the chain increases which increases the torque and hence the counter torque on the other end of this rigidly behaving part from underneath. This also explains why the height grows as the chain motion progresses

[@KingTairun]

you don't get a heart lol seems Steve don't like to be wrong

[@tscook10]

@@kabsantoor3251 But how does this fit with Medhi's demonstration of the 2d effect where there is no equal and opposite "pushback" on the chain? Or the observation that you start to see part of the chain leaving the "pool" and sort of hovering before it is accelerated upward into the fountain. This is why it appears that this effect is negligible, and the tension is what's important here.

[@SolomonUcko]

9:24 It looks like it *does* work with regular chain, just more weakly.

[@salinora0]

because regular chain has much more friction when touching itself compared to a ball chain, it snags on itself and slows it's own movement down, resulting in this weakened Mehdi effect, i am calling i the mehdi effect, because i believe mehdi is absolutely correct.

[@flavioromano8754]

You meant weaker

[@J_Kleb]

It does seem to grow about 4-5cm on the chain.

[@geoff3610]

the regular chain appears more to self syphon than to fountain, imo

[@dorerudoryuu2024]

This is what I've been waiting for all my life, a video about people discussing about a certain phenomenon that is currently unexplainable at once and people thinking of possible conclusions

[@kinomora-gaming]

"It doesn't happen on regular chain" >shows footage of it happening on regular chain I think the reason it happens on the bead chain (better) is that the radius of the minimum curve is larger than that which a regular chain can achieve.

[@unfunny2258]

way less friction and getting caught on itself as well

[@madamguillotine6819]

A simple answer.. Elegant I think you win. Ball chain is a series of ball and socket joints with limited angle of rotation. GOOD OBSERVATION

[@timalexander1811]

Also maybe because the bead chain has more parts per length

[@Svettulf]

Meme arrows on KZbin?

[@AdricM]

bead chain is also a heck of alot lighter per link than any chain will be, so that may be a factor too.

[@dylandailey3191]

Regarding measuring the weight of the beaker as the chain flows out, this should be something a certain electrical engineer should be able to accomplish. Just place the beaker on a strain gauge, and monitor the output of the gauge on an oscilloscope. Should give a very nice time-domain plot of the weight of the beaker.

[@angrymario8259]

Yes

[@lucianodebenedictis6014]

You need to accurately weigh the specific weight of the chain and the speed at which it's uncoiling to subtract that from the function or it will just appear as a slightly heavier chain

[@Kojo2047]

@@lucianodebenedictis6014 but if you track that change over time, could you work out if the chain is "changing" weight at any given moment? That would show that there's some force at work on the scale other than just the weight itself. If you know the weight of the chain, you should be able to subtract that from the results to show the discrepancy.

You can do the experiment with two different chains with similar weights: one that exhibits the Mould effect and one that does not.

[@Shocker99]

@@Kojo2047 and @Camelia Sinensis have explained the same thing but with different wording.

[@Edward256]

I kinda figured that the stiff nature of those metal beads with metal links added to the delay of them making the u-turn. Yes, when you squeeze them it looks like they could clear the pot's edge without problem, and they do at first, but as they pick up speed there could be some minute collisions between each bead that eventually delays the u-turn even more allowing them to maintain their "up-pulled velocity" for longer. But that's just my theory there.

[@robmack519]

Steve's eyes and my eyes must work differently because I absolutely see the effect happening with the other chains, just not as much. I think Mehdi has it that the energy losses from the chain's shape are dampening the effect.

[@GeeklingNo1]

When I heard it only worked with metal chain I immediately remembered the way it could bend only so far and I assumed it had something to do with it. It’s cool that this one fact that fascinated me as a child ends up being a key part of the problem. I got the idea even if I didn’t know anything about the science.

[@matthewmea3566]

yeah that was my first thought when i saw this vid.

[@thetruthexperiment]

Metal chain… ball chain. Almost all chain is metal.

[@GeeklingNo1]

@@thetruthexperiment yes indeed. That was probably the rudest way to say that. Thanks.

[@Darriuss87]

Just my thought, but I feel like the upward growing curve is still being caused by gravity. Because each ball in the chain is linked, each one in the sequence has to be moving as fast as the ball in front of it, and in order for the chain to get over the lid of the beaker, it first has to travel upward. Since each moving link has to maintain the same speed as all of the other moving balls, they're being pulled upward out of the beaker at the same increasing speed as the ones that are being accelerated by gravity(moving closer and closer to terminal velocity), accelerating them upward and out of the beaker faster and faster. I'm going to guess that the size of the curved area coming out of the beaker is limited by how far the chain can fall before hitting the floor, which I feel would stop the chain accelerating, and more or less level out the speed at which the chain is falling? As far as this not working so well with a linked chain goes, since the links can freely create gaps between the areas where they would each be contacting one another when in tension, the acceleration gets limited from a loss of energy when the links collide into tension, perhaps? I dunno, just taking an educated guess xD

[@jeansolal1264]

This was my guess too, although his explanation by the end seems to make sense too (the rod chain example) If your theory is correct then the chain should eventually reach a terminal velocity and not grow any taller

[@JordanNiks]

Interesting hypothesis. I see a hot air balloon and a chain long enough for the first dropped portion to reach terminal velocity while still having enough chain in a “beaker” to observe a plateau where the chain loop doesn’t grow.

[@themonsterunderyourbed9408]

I kind of agree, but the ball chain is different than other chains because it's stiffer. You can't have it fold back on itself like normal chain because it's little rods between the balls. The ball chain doesn't move as fluidly as a link chain.

[@ntp5358]

That would mean that eventually the fountain would stop rising, right? Maybe that's worth testing...

[@synergy021]

@@jeansolal1264 Absolutely this. It would reach a max height at terminal velocity. The height is a direct correlation to the acceleration of gravity and the forced upward direction.

[@davephillips9360]

Brilliant Mr Mould! Thank you I have learned so much from your work so far and share with my children and grandchildren. Keep it coming you genius 🙏

[@venmasters21]

Steve Mould: "Einstein doesn't have an effect named after him." Bose-Einstein Condensate: :/

[@deepeshpatel26]

😂

[@strahinjastamenkovic4327]

en.m.wikipedia.org/wiki/List_of_things_named_after_Albert_Einstein

[@GaryFerrao]

if only photoelectric effect was named Einstein effect 😂 Technically, i don't think there's an Einstein effect. Although, there are lots of things named after him; and in retrospect, they named a chemical element after him (waiting for Mould-ium now 😂)

[@strahinjastamenkovic4327]

@@GaryFerrao Einstein-de Haas effect?

[@GaryFerrao]

@@strahinjastamenkovic4327 argh you're right

[@Lambda3141]

Why send billionaires into space, when we can send these two amazing gentleman. They can play around with chains to their hearts content in zero-g!

[@CmdrGamagosk]

Nice name! I love the icon, hope you got it from the game files.

[@jro2020]

because these two can't afford to pay for it themselves duhhhhhhhhhhhhhh

[@rjsiii3]

He made some great points in his 2D model. Even showed the effect on other chains. Great collaboration

[@user-221i]

But I think it's due to friction with floor that holds chain.

[@NicholasproclaimerofMessiah]

I'm rather confident that the straight bars between the beads transfer the downward force on the falling side of the bend into upward force on the pot-side of the bend. You've done a good job of drawing out the details which make this rather apparent.

[@aniksamiurrahman6365]

9:26 doesn't look like it only works with bead chain. The footage you're showing clearly shows chain fountain with non-bead chains, only the height is very low.

[@Auttieb]

Exactly, the tension explanation makes no sense in this context, a momentum model makes a lot more sense

[@redskin_oi9968]

I may be missing somthing probably since english is not my first language, but I think he is talking about the kind arch that the chain forms in the air and doesn't rest over the border of the recipient at any moment.

[@im.g4ce]

one thing that I've noticed after watching both Mehdi's and Mould's videos is that both of them agree to be sponsored by KiwiCo

[@Its.a_me_]

I agree with Mehdi's explanation

[@Will-kt5jk]

But what does Kyle think? (he does have experience with long chains making loops…)

[@Its.a_me_]

@@Will-kt5jk I don't know

[@JaydragonM]

Im at 9:16 and I think the reason the chain rises is due to conservation of angular momentum. As each link leaves the container it begins to spin in a horizontal plane as it rises towards the high point, as it begins to crest the high point the link in front of it applies a torque and due to conservation of angular momentum, that change in direction results in an upward vertical force via the right hand rule.

[@JaydragonM]

And the chain follows the same path for the same reason. Conservation of angular momentum will cause the chain to consistently follow the same path - except the upward tension will increase linearly, and alter the shape of that path.

[@jameshansen1903]

This effect works on coil cord and the Cambridge theory doesn't explain why.

[@charliegreen3509]

I thought about that too but I'm not sure that's true: Coil cord probably has a maximum it can bend. We could replace the rods in the model with slightly curved rods and would expect similar result. Potentially it interacts with the width of the jar also. Also, even when the cord isn't maximally curve it probably has a restoring force to put it back to straight. This flexibility would dampen the push off force but not completely.

[@tscook10]

@@charliegreen3509 Yeah, I'd actually expect it to work better with cord, as you said

[@clancywiggum3198]

@@charliegreen3509 IMHO the minimum bend radius of the ball chain is slightly tighter than the radius that it's bent to in the slow motion shots so I'm not convinced it's acting as rigid levers - Mehdi alludes to this in his video too.

[@charliegreen3509]

@@clancywiggum3198 perhaps. Though perhaps it only sometimes is rigid and perhaps the camera shots didn't get this. Either way, my comment wasn't saying it does act as a lever, but merely that a flexible cord can still generate a force by a similar mechanism

[@mickoz84]

9:18: I feel you still can somehow see the effect on the regular chain, although only slightly. There are probably some other factors, like weight per length and flexibility. In Medhis video it can clearly be seen that the force agains the container is not needed to cause the effect.

[@unclebach3495]

because regular chain need more starting speed or start without a wall to absorb energy, if he use a very tall beaker to start the bead chain at the bottom it will need even more force to start, this is why Mehdi is right

[@charliegreen3509]

I'm almost certain that the extent of the effect negatively correlates with flexibility and positively correlates with weight of falling bit (I think the length of chain need only be so long as to get the effect in full (it seems to cap long before chain runs out)) [To be more clear, I mean: Weight of falling bit = weight of chain per unit length × height of drop]

[@unclebach3495]

@@charliegreen3509 agreed , and I think Steve is wrong about plastic chain, at enough height to let longer plastic chain to have enough weight to generate downward force it probably will work too.

[@vyomab515]

Congratulations on the discovery, Steve! It must be feeling amazing. With all the discussion going on, don't forget to acknowledge how incredible it is to observe and be able to contemplate on physics with such experiments. 🌼

[@XDMtube]

the “aha” moment I got from this video was better than anything I got out of my highschool classes, thank you steve for reminding me learning is fun when you’re interested

[@SimoWill75]

When I first saw this effect I imagined it was a stationary wave. Similar to when you flick a wave down a rope, except instead of the wave travelling down the rope, the wave is stationary and the chain travelled around the wave.

[@bradphelan8869]

I was going to add exactly the same comment. It needs to be modelled using wave mechanics rather than static forces. You also see similar effects when fast moving water hits slow moving water. You get a standing wave.

[@tachzusamm]

Absolutely what I thought. I think wave effects are totally underestimated here. I mean, you can't describe why a guitar string swings the way it does by simply looking at forces at a single point. Forces at each point of the chain are slightly different to those a micrometer apart (before & after). Kinetic energy and momentum spreads itself at each point forward and back, to each point forward and back. Imagine you fix the end of the chain at the bottom of the beaker, you start with the final situation "chain hangs down" - and then you induce a movement at the bottom end on the ground. It will run up the whole chain until it reaches the beaker. Each wave will run the same way from bottom to top. Now think about the fact that each ball on the chain accelerates on its way down - which must have an influence to those balls currently higher. Well, true, that's not a complete explanation, but maybe you get the idea. Additionally, I think it will not work the exact same way with plastic beads (pearls) and a fabric string, because fabric is much more flexible and would eat up more of the resonance effects. Anyway, you can see the same effect even with plastic / fabric chains; the effect is much smaller, but still visible.

[@dereksong2517]

Let’s can get Chris Hadfield’s attention, maybe he will help arrange that test on ISS

[@aidynproctor7137]

It wouldn't do anything in microgravity

[@TheGeoffingeorgia]

@@aidynproctor7137 I’m not sure I agree. It wouldn’t do it from a gravitational perspective, I.e. “towards/away from” the earth, but it might “rise” away from the lip of the container if it was in a loop with a drive cog. Further, if the chain was pulled in the opposite direction of the opening of the cylinder, and without the full effect of earth gravity, the entire lump of chain might possibly rise out of the container together

[@scottgriswold384]

Or just book a parabolic flight. A little cheaper and lots more room to test.

[@chris2944]

@@aidynproctor7137 you’d have to provide the force yourself but surely it would still work

[@ymj4256]

Or Scott Kelly He's also famous

[@j8rr3tt]

Because the balls float on the pins that link them together, I think it's somewhat of a newton's cradle effect as they spill out. The balls are going up as they leave the cup, and they bump into each other as they leave/go up and it keeps building up energy making them go higher and higher the longer the chain.

[@keineangstable]

This is the right answer.

[@Arkanic]

Got to go with Mehdi on this one, looks like the same wave effect you see with whips to me. The reason the chain doesn't rise as much is most likely all the extra friction.

[@jama211]

Yep, me too

[@ZearthGJL]

"This enraged his opponent, who punished him severely."

[@julienckjm7430]

🤣

[@willandersen3695]

Underrated comment.

[@zachj61]

Thank goodness you mentioned the metal bead chain being unable to bend too far. I thought it might be critical to understanding this phenomenon. Now to await a bigger scale experiment with a stronger chain

[@dana102083]

I played with these a lot as a kid and that was the first thing I thought of. Id try to undo a clasp with one hand by forcing it to its max bend. Physics..not so much. Its more interesting as an adult now.

[@sknopster]

Steve, I'm sure by now you understand that "plastic beads" themselves are insignificant. It's the fact that the plastic beads are connected by string which can bend very tightly. Whereas the metal pins used to connect the metal beads are essentially rigid; on that scale, and with such minimal force applied the pins are not bending past the point of permanent deformation. Therefore, they transfer the force that you've described and demonstrated e.g. shooting the block on center vs. near one end. It also occurred to me that there could be a certain amount of spring action within each length of pin or wire in combination with the metal beads. Whether or not that extremely tiny amount of spring resistance is significant... Well, that would take a mind on par with a Mould or Einstein! Btw, You're a rockstar!

[@moonlight2870]

"The fountaim effect doesn't work in regular chain" *shows a clip of it clearly working on regular chain*

[@scaper8]

Yeah. It may be less dramatic of a visible effecr, but it does still seem to be present. I think Mehdi has the right approach here.

[@nathanmorazan7775]

Plus it doesn’t rise in height like with the head version usually staying the same height

[@blockstacker5614]

I believe the effect was first observed in a regular chain, in fact.

[@asharak84]

was a really odd section. Especially as, given the kickback explanation, a regular chain should also work.

[@scaper8]

@@asharak84 Not just work, but work better. If there's a leverage effect, then an actual, ridged lever should make the effect _more_ pronounced, not less. EDIT: Just as I typed that I realized that it is possible that the extra weight from the links could counteract the extra force, but either way, it just doesn't add up.

[@arthurnonimus]

I think you may have to pay up soon. ElectroBOOM's 2D floor model is quite convincing.

[@jama211]

Steve's main issue with it is it never went 'higher' (or to the right) than the initial state, which is not true with the beaker. But, I think this is overcome-able if Mehdi can make a lower friction version of the 2D model - and also compare to one where the chain "pile" can't go down (to the left) because of a blockage - this would compare the two. I mean, I'm with Mehdi here, but for all we know it could be BOTH? Some force from leverage, some from momentum, right?

[@blahorgaslisk7763]

@@jama211 There is also the question of accelerating the pull on the chain. Mehdi can just run that fast while the chain falling will accelerate for a pretty long time. The added velocity will cause the chain "fountain" to rise higher. Also remember that for interesting reasons the chain will accelerate faster and have a higher terminal velocity than a simple object like say a short segment of that same chain. So Run! Mehdi. Run!

[@getaclassphys]

Our old video with an explanation of this effect (in Russian, with English subtitles). What do you think about this? kzbin.info/www/bejne/qnLCdHp-jLKgn6s

[@floriot]

And it looks like you used plastic beads with string in between.

[@getaclassphys]

@@floriot sure

[@LucianBlankevoort]

I think yours is also an interesting theory.

[@Drew_Hurst]

Footage from 2012... I hate to say it, but it seems like @Steve Mold didn't discover the effect

[@getaclassphys]

@@Drew_Hurst Usual situation, don't hate anybody.

[@CC-gu3ze]

The rigid connector rods between the beads are the key factor. They can take tensile and compressive loading, where regular chain and string cannot. This allows the beds to exert a moment on one another that lifts the trailing sections and magnifies with the number of beads in motion. The effect would also be neutralized if the beads allowed more range of motion for the connecting rods to pivot, like a ball-and-socket connection.

[@Xenon49747]

This effect is almost like watching the initial wave flowing through a whip, and there is a ton of math and research studying the physics of a whip. It might be worth a look.

[@zorod5475]

The mould effect would be like doing the motion of the whip then running with the handle so the wave stays in the location it starts. And as you move away the wave gets larger at the whipping point.

[@zorod5475]

Could we get the mould effect by doing it with a rope with a weigh only at the end while it sits on an extremely high shelf?

[@eideticex]

Seeming like it's a whole slew of manifestations of a more fundemental effect. I mentioned it reminds me of nylon rope with a sinker weight, how it will travel through the air until it pulls the entire bucket of string if you don't grab the string to stop it. I noted however it's that the wave gets too chaotic at some point.

[@ptamog]

I totally agree.

[@ptamog]

@zorod Some weight needs to be distributed through the rope. Whips play with decreasing wheigh profile for maximun acceleration at the tip. And Meddy is right… just conservation of momentum and tension. More weight and less inefficiencies works better.

[@billallen275]

When I was a kid my uncle (a Chemist) sent me "Things of Science" kits. That was more than 50 years ago! So glad to see this stuff back!

[@tsnap4]

"It's been on QI..." Steve, you can't just drop such a high accolade on us.

[@josephcoon5809]

8:30 You can resolve possible parallax issues by using a light shining I cross the chain onto the measuring board and tracking the shadow. ​ 1. Chain falling down accelerates faster than gravity. 2. Chain flying up has the same acceleration as the the chain falling down. 3. Chain flying up accelerates faster than the negative acceleration due to gravity. 4. Chain flying up has a net positive acceleration. -c = acceleration of chain falling c = acceleration of chain rising -g = acceleration due to gravity -c < -g c + (-g) is positive meaning the chain rising has a net positive acceleration upwards.

[@Ferro3D]

What this effect is is just a wave, like the ones you could send down a length of rope. In fact I'd argue that it's exactly the same but instead of the wave traveling along the length of the rope the wave stays stationary as the rope travels through it.

[@FunnyMemes-dr3se]

Lol the Veritasium bet reference. I love how the science KZbin community is so close.

[@rfreaky4717]

9:33 "you dont see it with regular chain" and shows video of it on a regular chain (well weaker but still there) I think it would even work with a rope if you put a weight on the end.

[@nesrasiti]

Perhaps the fact that the spacing between balls expands starting out and contracts falling down is the answer creating a whipping effect

[@rasput1n6]

*9:20** "It doesnt work with other chains", while showing that it WORKS with other chain xDDDD* *The effect is there!!!! it's just not that much as the other chain, but it's right there!! Come on man!! The chain isnt even touching the glass for seconds on this drop **9:20*

[@LolSho0orTs]

@@lilkingtrashbaby true

[@genstargate5249]

@Fk Gooogle At least to me, it seems like the climbing effect is less pronounce when the chain links are larger because the individual links are heavier and the eddy currents of the air that could be produced by the oscillations of the chain as it leaves the container walls are not as large.

[@MikeSchlueter]

@@genstargate5249 I think the effect is also less pronounced because it's losing a lot more energy to displacing other links while the links are going up. Did you see how much the other links that are still in the jar were moving around as the chain went up?

[@marcinpietrzak9358]

@Fk Gooogle It is climbing - notice that the starting point is constantly getting lower and lower, but the loop is not.

[@madmodders]

The patterns you're talking about at 18:35, also happens to ordinary chain. Happens all the time when you pull the chain fast on a manual chain hoist. :)

[@theotheroneb1548]

9:22 "you don't see the effect with regular chain" proceeds to show it happening with a regular chain

[@Cketzalcoatl]

Yep. I think Steve should use very shallow bowls or putting the chain on a table or something. Some chains "jump" less than others (due to friction, etc) and if the lip of the pot is taller than the chain jump height then it just bangs on the lip.

[@lucdesnoyers645]

This

[@Omega_Orion]

I think the issue with the forces you provided is within the frame of reference of the chain, there is a constant and growing force that initiates the movement in the first place. Maybe once I wrap my degree I'll have time to try and model the tension of the falling chain. I'm pretty sure that explains why it takes time to get into the highest arrangement, and why that height changes depending on how high the chain is falling from

[@Mirgolth]

5:21 Steve, why would you wear your gloves on the wrong hand (Right glove on left hand) ?

[@leventgencer]

The question that truly needs answering.

[@Khantia]

To trigger people who are paying attention to such things :D

[@beyond6storm]

go up, I need to know if it's because of what I think it was

[@hardyworld]

I remember when I was a kid (25 to 30 years ago now) while playing in my dad's shop and I made the exact same 'discovery' as Steve made in his original video. I kept experimenting with different chains and different lengths and different fall distances and came to the same conclusion Steve did concerning everything he mentioned (only stiff chains rose up, longer chains/fall will rise higher, etc.). I remember asking my dad about why it does that and he said it was the momentum transfer that pulled the chain above the barrel and I challenged that saying these chains that are more 'loose' don't rise up the same way. His response was it was the still momentum pulling it up and that those loose chains don't rise the same way because of the loss of energy along the chain in those loose links. And I took that answer as being correct for a full day. Then I told my dad the next day that if the momentum was pulling it up higher, then that means the downstream side of the chain's peak would be pushing the chain up...and that doesn't make sense. My dad agreed. So we believed some energy kick must be coming from the bucket when each link is jerked upon. We were satisfied with that answer. Good to see people smarter than my dad and I are getting to the bottom of the cause of the observation many people have made over the years. The explanation at 13 minute mark makes a lot of sense to me. I don't know if my dad remembers our discussion about this subject, but I'll send him this link anyway.

[@zachreynolds8903]

Well if anyone has conections to the space station it's Destin from SmarterEveryDay.

[@everyweekmemes9178]

And the only one who has connection to Destin from smarter every day is Barack Obama

[@marioghioneto1275]

@@everyweekmemes9178 god I love the internet science community

[@mcnuggetwarrior8218]

What about Mark Rober?

[@zachreynolds8903]

@@mcnuggetwarrior8218 very true

[@Jiglias]

@@mcnuggetwarrior8218 didn't he literally work for NASA?

[@con.troller4183]

You can see the chain twisting and turning in the jar as it orients to the falling chain. I think this is because the chain is randomly stored in the jar and loses energy reorienting as it is deployed. Like a garden hose getting twisted up if you don't keep releasing the tension while coiling it up. Perhaps if the chain were loaded into the jar in a more orderly fashion, and the internal tension of the chain was reduced, less energy would be lost during deployment and you would get a greater height.

[@gabrielhacecosas]

I watched your video earlier and it seemed to me that you were right, but then I watched the electro boom video and it seems to me that he is the one who is right. I also realized that the leverage system that would make the ball jump out of the pot would do the opposite when hitting the ground, so those forces cancel each other out.

[@Khantia]

I'm afraid ElectroBOOM was more convincing in his arguments.

[@LeoStaley]

He showed us why chains have self sustaining fountains, like the one at the end that he gave a boost to, but didn't tell us a dang thing about how a chain would start its own fountain and, moreover, GROW.

[@zsomborhollay-horvath4602]

The good thing about science is there is no need to be convincing, you just have to be right

[@Toalen]

@@LeoStaley he actually did, the chain keeps accelerating as it falls down so the distance it has to travel has to be greater in that same time difference to not have infinite acceleration, so the chain rises. He did not say it explicitly but he gave all the reasons that explains why.

[@LeoStaley]

@@Toalen but his alternate chains and demonstrations DID NOT DEMONSTRATE SELF STARTING AND SELF GROWING. The horizontal one actually shrank!

[@Toalen]

@@LeoStaley That is correct but both of those tests had not ideal maximum speed / frictions. It was only 3 meters high and medhi running with the chain touching the floor. Additional tests need to be conducted. @when ISS test

[@ThwriktoKavlerwf]

Mehdi's explanation seems more logical. the 2D experiment convinced me.

[@1TakoyakiStore]

Agreed. Surface resistance seems to play a part in restricting the effect.

[@harrymarlow8409]

And the way it’s laid out on the floor. Like Mehdi said “ the chain can tangle losing lots of energy” he’s got my vote on who’s right

[@cate01a]

yeah but tbf I understand neither explanations - also, in the comments, mould poses some interesting statements; specifically, that the chains in medhis experiments sometimes don't actually get larger/rise, and therefore there's no mould fountain, but rather just the conservation of momentum, chains following their pattern. And in that is interesting, like with medhis floor experiment, the peak indeed doesn't increase; however, you could think that the peak's height is relative to the beads waiting to move, and in which case, then maybe the peak is constant or rising.. who knows!

[@sneakyfildy]

Oh my god, being in a rocking bucket so high 🙈 looks like a nightmare. You are a very brave person! 💪

[@omamchy]

So satisfying. Totally worth it

[@DoubsGaming]

"normal chains don't do the effect" *shows footage of the effect slightly working*

[@movin3148]

That apparently isnt the effect, the effect is that the height of the loop increases as the chain goes faster.

[@bambamfpv1102]

The effect is less pronounced

[@JeffNipp]

The effect is there... It is just damped by the chain snagging on the edge and on the chain itself. I think Mehdi did the definitive set of experiments. But if one disagrees, a cable of significant weight but good flexibility would do it.

[@Phunkophil]

You know a physics argument is about to get real, when you bust out the small angle approximation. A man of true culture!

[@tyler-simoni]

It reminds me of wave physics through a rope or chain. Instead of the wave moving down a stationary length of rope/chain, the wave is stationary while the rope/chain moves away from it.

[@michaelwerkov3438]

as i was reading this, 18:50 happened, where he said "instead of a pattern moving through the chain, the chain moves through it." basically equivalent to what you said. i'm not a math guy, but i wonder if there is some wave equation equivalent?

[@laurabrown851]

195.201.34.87

[@charlestaylor3195]

Is it a standing wave?

[@theknightoftech6283]

15:38 Could you hang a bucket on the scale, so the scale is measuring the bucket that the beads are falling into as well as the bucket they're falling from, and see what the fluctuation looks like?

[@black7rc720]

Steve, how is this "Mould Effect" different to the effect that causes the tip of a whip to break the sound barrier in free air?

[@MarsMountain]

I also think it can best be described as a chained whiplash effect, pulling the rest of the chain up. Looking carefully, the end of the chain goes even higher in the air since there is no more chain in the glass holding it down.

[@brandonloukota4760]

The tip of a whip speeds up because of conservation of energy/momentum. You move a thick/heavy part of a rope as fast as you can, and then as the ripple moves down the whip the whip gets thinner and thinner but carries the same energy. In order for a lighter section of the whip to have the same kinetic energy as the heavier section is has to move faster. So the wave gets faster and faster down the length of the whip

[@thomasi.4981]

I absolutely agree, this is a *lot* like a whip. I was going to post another comment but I'll bump this one instead.

[@parkinfurkmaz2877]

@@MarsMountain What the, that's not explanation for why the chain goes even higher in the air. The chain leaving the beaker isn't coming from the bottom of the pile; it's coming from the top! It doesn't matter how much chain you have in the beaker; it shouldn't affect the height of the fountain. Plus, both Steve and Mehdi have done plenty of experiments at low heights showing that the fountain's height is roughly constant after it initially gets going. With your explanation, the chain should always be rising as it's leaving the beaker. Not sure how you came to that conclusion since neither Steve nor Mehdi proposed that to be the solution (and it's kinda obvious that that's not the answer).

[@black7rc720]

@@brandonloukota4760 How is it different? Not, can you explain what causes the whip effect. That is why Steve climbs 50m...to increase energy. Potential to kinetic. The further the drop of the chain, the higher the "fountain" rises.

[@StephenHind]

ElectroBOOM is right I'm afraid: his video pretty much proves it

[@RobertMinkler]

I have to agree

[@samuelmacdg]

I agree

[@iain_nakada]

Don't agree. There are 2 separate properties here - the propensity of a chain to maintain it's shape while 'flowing', and the creation of the upward loop against gravity (the Mould effect). I think Electroboom's video pretty much exclusively shows the former.

[@bountyjedi]

9:20 To me it kind of looks like they're still doing it, just to a lesser extent. There are periods when the chain doesn't hit the lip of that beaker. But then at times it hits it, and it slows down a bit.

[@PeterLE2]

WTF How could I miss this amazing channel and this Mould effect videos at all. Real great video

[@babylonfive]

Need some SmarterEveryDay action here too.

[@jim-171]

Yes, get Destin involved. I'd like to see the chain pot on a scale, and use the slow motion footage to calculate the mass of the chain leaving the pot, and then cross referenced with the refresh rate of the scales to determine any downwards force. Also, Destin would be in a pretty good position to get the attention of NASA and see the experiment explored in space.

[@aldod8167]

And in 20 years time Tom Scott can explain to us how this was used to somehow end climate change.

[@Twigpi]

The dude loves laminar flow - I'm sure he'd love to explore this as well.

[@disenchanted3724]

He bothered to destroy the physics of domino fyi

[@sghsghdk]

Mehdis 2D tries proved that the fountain also happen for the regular chain. I would belive that it would happen for flexible steel wire (if such thing exists) as well.

[@cate01a]

flexible wire, aka cooked spaghetti

[@sghsghdk]

@@cate01a I'm guessing that spagetti does not have the strength do cope :)

[@IgorKravets81]

I suggest to contact Adam Savage - he used to have astronaut connections!

[@rampage3337]

i think i have even seen adam savage do this like a billion years ago. im pretty sure that one of the mythbusters episodes they showed this off to explain somthing that was going on in one of the myths. i think it was somthing with water flow or somthing

[@johngerken4263]

@@rampage3337 yea, I remember that. I thought the episode was actually focused on explaining this effect though. I don't remember anything about water flow...

[@mimimi9170]

@@rampage3337 I agree with you

[@kori228]

@@rampage3337 looks like that episode is from 2014, so after Steve Mould's video! Steve's video might even be what made Adam and Jamie test it.

[@LeoStaley]

Pfff, matt parker has done videos with astronaut Chris Hadfield.

[@droesable]

Doesn't the "extra energy" come from the springyness of the little steel rods in between the balls, as they are slightly bent during the pull and therefor act as springs when they are straightened? Also when you show the smallest curve they can make at 14:11, those bals are much closer together, because there is no "pulling force" keeping them at max lengt.

[@fluffigverbimmelt]

13:13 me, a European: The rod jumps, like an ollie with a skateboard Americans: Like a brick shot from below at an angle

[@pompeymonkey3271]

I was put in mind of ollies too!

[@kjohn5224]

skateboarding is american, wth are you talking about?

[@greggv8]

We Americans are more interested in macro physics experiments when firearms are involved. ;) Regarding such, before electronic chronographs were invented to measure the speed of bullets, a massive swinging pendulum was used. The pendulum was made to capture the bullet for maximum energy transfer. By using a set distance from muzzle to pendulum, and accounting for air pressure, temperature, and the mass of the bullet, measuring how far the pendulum swings then using that value in the equation gives the velocity of the bullet. Testers back then wrote all that down and published the velocities in books for commercially produced ammunition. Much later, someone decided to replicate the process and found all his results were slightly off from an electronic chronograph measuring the same shots. But then he thought "What about the very tiny layer of air the bullets drag along on their surfaces?" no way they could have considered that way way long ago! So he did some research to find out the mass of the dragged along boundary layer of air and subtracted it from the right place and the velocity values matched the electronic chronograph. Thus the pendulum test was proven to be an accurate method of measuring bullet velocity and you can trust the old data books aren't being somewhat optimistic on ammunition performance.

[@XRioteerXBoyX]

@@greggv8 That's a great comment, I'll just leave a reply here so that I can return to it again at some point in the future to marvel at it again.

[@fluffigverbimmelt]

@@kjohn5224 i knew this was gonna come