Thanks for all the suggestions that went into this video! What do you think? Convincing? You can also discuss this video on REDDIT: stvmld.com/n26_w4an And can I just point out this brilliant video that came out the day before this one and has a lot in common: th-cam.com/video/I31GfljDEWA/w-d-xo.html The sponsor is Curiosity Stream: Get a whole year for just $14.99 curiositystream.com/stevemould
There is another thing to consider may be, That the chain colecting cylinder From 6th min the left one vedio collects the chain at one stop only making the radius of a chain collecting at a given time increasing Where as in another case the right case the chain is collecting overall the cylinder so, the radius of chain collecting at a given time is constant And so, at left vedio case peak may constant and in right case peak is reciding .
The inertia from the rising chain is what’s doing it. You are tossing the links in the air. There is clearly a minimum velocity required for enough energy to clear the rim. I first thought it was the internal levering of the strand of chain at first also.
i think you neglect the centrifugal force playing in the moving loops (because there are smaller ones before the top one), whipping the chain around. The chain has a substantial speed in the loops.
Maybe they just both present compelling arguments? No need to doubt yourself. They're both giving evidence for their assertions and they're good arguments
I think Medhi's first video very legitimately pointed out real flaws in the experimental evidence Steve provided. The experiments really got refined a lot over these videos, but unfortunately for Medhi, the experiments still agree with Steve. But it was too easy to go from "experiments were flawed" to "theory was flawed".
This all was the purest definition of “I respectfully disagree, …” Except, in Mehdi’s case it’s “I respectfully disagree, despite your mesmerizing blue eyes and soothing voice…”
This is a great demonstration of why disagreements are good. Sure, one side is wrong, but it drives the other side to go into far greater detail about things and in the end you're left with a much better understanding of the problem. It's beneficial for everyone.
The individual beads on the chain would experience constant acceleration during the event from start to finish. The bead centre of gravity stays the same while the overall systems centre of gravity changes. This leads to a whipping effect. If you hold the bottom of that chain and use a whipping motion upwards the beads would rise proportional to the energy added from the system. It would create an arch exactly the same until all the beads left the pot
Former industrial rope guy here. Watching this series reminds me of observations made at a film set that involved passing thick rubber coated power cables down a cliff. Care had to be exercised once a certain amount of cable was payed out as it would quickly become, and I’m being extremely tame in my description: “self lowering”.
Honestly he seemed pretty honest and credible up until that point. But manipulation tactics should never be used in arguments. Now it seems like he cares slightly more about winning than getting it right - getting it right is just a crucial part of the persuasion. And you shouldn't trust people with loaded motivations on any sort of thing based on truth-seeking, should you?
Is it bad that I want ElectroBOOM to find another hole in your explanation? Not because I really care that much about whose right (I just wanna know what really going on and I don't care who finds it first), but because this playful back and forth is one of the most fun YT collabs I've seen in years.
@@IRNoahBody sorry, can't make sense of what you wrote in the last part, but I would take the conclusions of a computational physics program over an enraged guy with a little whiteboard to calculate extremely complicated real life physics. Side note: 3D CGI effects for movies/animations where cloth and hair is flowing in the wind, and even mind-blowing realistic fluid dynamics like a flood rushing through a city is all generated by a computer physics engine that can develop and render a realistic outcome all on its own, and could never be achieved by an army of humans without the aid of the program. It also wouldn't be possible to achieve by a guy with a pen and whiteboard either, no matter how enraged he got.
for me that is the simple answer. the falling part of the chain speeds up generating more chain tension than the rising part. This is implied by the fact that the chain fountain is rising because the greater tension (force) causes the chain curvature to straighten more quickly on the more stretched side, causing the curvature to move upwards against gravity. In short - the side that is pulled more eagerly and faster straightens, which causes the curvature to shift in the opposite direction to the pulled side.
This has nothing to do with peer-review though. The reviewer is not conducting their own experiments. This shows though how productive healthy competition can be.
Peer review is the evaluation of work by one or more people with similar competancies. It’s true academic peer review for a scientific journal wouldn’t do a replication study, But the disputes come from reviewing each other’s work and criticizing. They are playing to more than just each other, they are also playing to an audience, an audience who grew up on myth busters and bill nye, not rigor. They demo. That’s what these videos are are, science explanation combined with visual demos that function as experiments. The criticism of experimental technique and challenging unproven conclusions, is key to peer review. The shown visual experimentation is for an audiance who doesn’t grasp the concepts well. As the myth busters showed, visual science sells. But gussy up the videos, supplement to visual demos with a lot more rigor, and the actual criticisms lobbied back and forth are review of the of the works each put out. It’s peer review, it’s just not academic peer review.
@@muuubiee my point was that the back and forth we see here is not what is meant when scientists talk "peer review". This is related, more akin to replication.
Basically how AI got so good. Science is all about blind agreement now and that will get us nowhere. Just like how the Chinese closed themselves off and ended up being owned later by a civilization that came up with new ways of doing things
Idk what is wrong with me but its like the 5th video about a metal chain falling down and somehow i get more excited with each one XD, ty for keeping my brain off of my engineering degree
Absolutely nothing wrong. The drama of the twists and turns of points and counter-points as we swirl around the solution to an interesting question is quite reasonably very exciting. A simple "metal chain falling down" may not be all that interesting, but this exploration of a curious phenomena and debate around it are far more nuanced and complex than merely watching a piece of metal get dropped : )
It would likely have been viewed as black magic or witchcraft and ended with the presenter being strapped in the ducking stool or rolled down hill in a spiked barrel....heretics😂
1:30 in slow motion I believe you can actually see this happening when it hits the longer chain link and you can visually see the chain react more aggressively because of the sudden change in overall stiffness
The best thing about this collab is that it shows the "normal" person how to discuss a scientific topic, and how easily you can become preoccupied towards either side, if they talk convincing enough. Thanks for being a good sport and an amazing role model!
You could easily align the footage with a USB force gauge by tapping the top of the breaker the chain is in before doing the fountain. Just align the spike in the graph record with the tap on camera. Same theory as clapping to align the audio with the video when recording from a standalone audio source.
You should also tap it again at the end, because the sampling rate is going to differ from the camera's frame rate and you need two points to scale their time axes properly.
I'd be curious to see if there'd be a (small) spike in the (graph of the) reading when the loop passes over the rod in the setup shown at 15:50 Edit: watching through 16:00 at .25 speed, the loop passing over the bar appears to be when the "additional" force is applied. I also really enjoy how clearly the pronunciation of "additional" comes across as "a-dish'-nal" (vs "a-di-sho-nal", etc.)
This might not work, because the scale display operates in "cycles". You may create the spike at the end of a cycle and measure a small delay, when if the spike happened at the beginning of the cycle, you'd have a longer delay. This might be able to be overcome, but something to think about
The essence of peer review is adversarial. My job as a reviewer of a paper for a journal is to try to find the flaws in the logic, design, analysis, conclusions, etc. I then report my evaluation. While not all reviewers are this way, I try to write my reports in a kind manner, but it can't help but come out with an adversarial tone because that's the nature of the peer review beast.
My reply: and what do you think? Just curious. Once the chain is moving fast enough, the rigidity in the chain is your lever, and that rigidity gives the large downward section of chain the mechanical advantage to lift the portion that is at rest, up. The “lever mechanism” IS the rigidity of the chain. No “kick up” from the container needed. When the mechanical advantage is large enough to overcome the weight of chain on the “up-side” or “at-rest-side,” the fulcrum can move up. The only force needed is from the tension in the chain on the “down-moving-side.” If the container were to be “kicking up,” the chain could start moving on its own. (Think of the rigidity in the chain like a bent 2x4 that is flinging the chain up from the fulcrum… the place where the chain is bent to some critical point (the fulcrum) seems to “spring up” the upward-moving-side because it is already moving upwards, and it is a shorter length, and is therefore lighter in mass relative to the downward-moving-chain.)
@Jack @Steve Mould The chain doesn't spring up on its own because there's no energy change in the system at that point. The energy ultimately comes from the falling chain (conversion from potential to kinetic energy), but the dynamics of it transfers to the just rising link in a non-intuitive manner. This becomes a limit to the speed of the chain and the height of the fountain when the force pulling down balances the resisting force of the rising chain. The reason for the kick up is the pull down which is converting potential energy to kinetic energy. Note that the 'fountain' effect increases from nothing as the speed of the chain ramps up. The speed of the chain will create a proportionate jerk on the end of the piece of chain entering the rising portion. Because of momentum on the entire link, it tends to stay stationary which means the link 'sees' the pull on one end as tending to rotate the link, meaning the other end has to push downward. That downward push then pushes the entire link up. That push up is proportionate to the change in momentum from zero to the speed of the pull up by the chain, and is added to the speed already set as an acceleration. As the speed increases the fountain rises to a limit because there is added energy.
@@lagautmd if there was no change in energy at the fulcrum, it could not rise. the fountain effect begins as soon as part of the chain is bent to its maximum. The downward force increases as the chain moves faster. The “downward-moving-length” is longer and heavier than the “upward-moving-length.” The point of the chain that is bent to maximum is the fulcrum and the chain links are like a teeter-totters. “Non-rigid teeter totters” ….. which can load like a spring. The unbalanced force is what gives the “spring” of the fulcrum it’s mechanical advantage to fling up the next link. I think much of what you said is in agreement with me. The fulcrum can rise because of the loading and unloading of the “springiness” of the rigidity in the chain. The extra force or mechanical advantage does not come from the table, but from the unbalanced forces in the chain. The rigidity in the chain is the lever, and that loads like a bent board.
Yeah, not the priestly arrogance of mainstream science. All we know is that we know nothing. Through Socratic argument (which got Socrates killed) can we discover truth.
Assuming both parties are being genuine, any scientific discussion should be pretty easy to keep civil. It's not about opinions or ideals about how things ought to be, it's about observations and understanding how and why things are.
because someone created a 100% accurate simulation of the universe on their computer to simulate the chains going brrrr, and it isn't just some random project he did in 1 hour tops
I love this debate playing out in the open. Too many people have no clue that this is how science really happens. On the other hand, I think some in the science community could take a lesson from the spirit of friendly debate being displayed here. Too often deep acrimony develops from disagreements. We should all be focused on getting the best answer, even if it means, in the end, that we were not correct in our original hypothesis. Honest open debate with supporting experimental evidence helps science (and in turn, society), character attacks do nothing but show the real character of the one doing the attacking.
@@pseudonymousbeing987 Paleontology kinda incorporates both science and exploration, the latter of which brings with it things like bragging rights and dick-waving that leads to lifelong blood feuds and libelous public spats. Look up Richard Owen.
Now imagine if TH-cam decided that this chain fountain issue was important to public safety so they banned Electroboom's videos, as well as anyone else's video who disagrees with the people TH-cam declares the "experts" on the topic. This is what is happening with discussions about COVID-19 and the vaccine. All discussion has to take place behind closed doors and isn't allowed to be transparent because TH-cam (as well as Facebook and others) have declared themselves the arbiters of truth and have decided for us which experts we shall exclusively listen to.
I don't understand why this doesn't have more upvotes. Although if the put a beaker through one of the windows on the ISS' cupola I think Steve and Medhi had better change addresses...
I first experienced this when I was very very young taking out Christmas decorations. We kept a long thread of red, wooden cranberries to wrap around the tree and one year I was unpacking it and WHOOSH the chain came raveling out of the bag making an arc. I must've been 6 or 7 so 2002/03. Very cool to see people talking about it. I assumed it was already studied!
This interaction between the two of you is a perfect example of why peer review is such a powerful tool in scientific exploration. Everyone has bias; it is unavoidable. And sometimes people just miss things. Great job.
sometimes the bias is just that you aren't explaining it very well, because you are biased in that you already understand what you are trying to explain. That is why they say you learn a lot when you have to teach something.
Man, these videos with the "friendly fight" are amazing. I've found your explanation more convincing from the start, but seeing Mehdi force you to really step up and prove it - while you do the same to those who think his explanation is more convincing - is just a lot of fun!
Science is supposed to be adversarial. That's what peer reviewed is supposed to mean. Most unis and r&d have biased sponsors that want a result and will pull funding if thier predetermined solution isn't "found" Real science is constantly telling everyone they're wrong while they all come at you full force to poke holes in your thesis.
Bear in mind (a) human eyes do that normally, which you can check with a mirror, and (b) he's holding the camera he's rotating, so his body knows which way things will turn next.
Scientists and those prone to scientific investigation used to do this via articles and journals. YT is a great medium and we definitely need more of this.
The only way to prove this once and for all is for Steve to explain things from the top while wearing brown contact lenses so we're not mesmerized by this blue eyes
This collaboration is like an inside look into the scientific method. I love the deep look into peer review. I would very much like to seem more of this amazing content.
To measure the force, I would recommend strain gauges, a Wheatstone bridge, and a USB multimeter. After you get past the annoyance of calibrating the strain gauges, you would have an accurate feed of force vs. time. (This is what early aerospace engineers did to get similarly accurate measurements of forces on wind-tunnel models) You could do it with well under $100 of instruments. Can't help you with the tedium of counting the chain links and time syncing the data to the video, though.
Probably tapping on the force gauge while video recording it will be a good sync point. I also found that if you have a very high impedence volt meter (~100 Mega ohms, like the adc of an Arduino uno) use can use a piezo speaker as a very sensitive force gauge. You might want to divide the voltage with ceramic capicitors in series. Also note that they technically produce voltage when the drum deforms into a bowl, not when it is squished. The crystal is grown radially.
LOL this comment perfectly enapsulates just how insane this has all gotten.. and I absolutely love it. Edit: btw, very engineer-y of you to considering how he can do your suggestion while still within the budget (well, the budget assuming he wins. And I realize that makes no sense for a monetized youtube video from a professional science educator, but you know what I mean!)
Strain gauges are a pain in the arse. I've used them in a full bridge before and got crazy drifts over temperature and still little sensitivity to the direction of interest. Getting pre-built gauges is the way to go.
Unfortunately that's not how peer reviewing actually ends up working in practice. Peer reviewing almost never involves recreating the experiments to validate the data or other relevant experiments to attempt falsifying the original, only that everything looks to have been performed and recorded correctly. It's less duplication for scientific rigour, and more editorial proofreading for science writing. It's still important for the validity and reputation of a journal, but it's not nearly as rigorous as the vast majority of people believe it to be. Especially when you get into fields like sociology where the majority of published research can't be duplicated.
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@@Meton2526 Alas, yes. And until recently, it was very uncommon to provide full data sets or full code with your papers. So in a sense, it was really just proof reading. Real world people in real world companies trying to follow along eg chemistry papers typically expect most stuff not to work. See NileRed's channel for a taste of that. And chemistry is still one of the harder sciences.
Damn, I love watching competitions between scientists. Especially if both have very reasonable arguments, but both end up wrong and open up more trains of thought
One could argue that the half-circle radius as given by the tension and velocity of the chain is at an optimum. In one of the clips he makes a motion as if with a whip. Does the tip of the chain react to force from the hand holding the jar before it hits the ground?
Should make you question the videos you watch elsewhere more! That said it could be a good thing, maybe you don't form opinions into unbreakable beliefs !
The additional force? Easy - acceleration! The falling chain is transferring its kinetic force into the static chain that has limits to his flexibility, attempting to pull it directly toward itself. But, being a flexible length it wants to follow the force that is already being applied - vertical acceleration. Once the vertical acceleration is overcome by the downward force of the falling chain it is pulled - in as much as its flexibility allows - back downward. Just like you'll see a bow in a whip as it is extending toward its terminal length. Since there is nothing at the end of that length all of the energy is concentrated into the tip, allowing it to break the sound barrier. The same applies to animals shaking out their fur. The abrupt change in direction over a short flexible length causes a snap which breaks the surface tension of the water adhering to their coat. Since the chain does not have that terminator, all of the acceleration energy builds in the curve until the very end of the chain (which, by the way, you never let us hear) which probably makes a pretty sharp little crack as it reaches the top of the arc - though the mass of the chain likely limits that considerably.
This is essentially what I think. They don't seem to be factoring in the accelerating force of gravity. And it's cool to me that the phenomenon expresses itself as a sine wave form. Not sure about your noise at the end theory, because I believe a whip's crack is caused by the tip breaking the sound barrier, isn't it?
I have an idea. What if instead of the wide mouth beaker, you piled up the chain in a long acrylic tube? Say a 12-25mm diameter tube. This would allow you to have a really long(deep) static chain, and see if the fountain still rises away from non moving pile. Its similar to your floor idea, but you get to see the same effect as the beaker setup.
This would be interesting to see, if the tube was longer than that meter high maximum he established in this video. Will there be no fountain as the chain passes over the edge of the tube?
Well he did have a long tube(50-60cm) in height for the first experiment th-cam.com/video/qTLR7FwXUU4/w-d-xo.html at 6:10 , But I guess it needs to be even longer like 1.5m
Thing is it wouldn't disprove mehdi because all he believes is that the momentum of the chain combined with its inflexibility at the joints causes the loop. No reactionary forces required. A deep tube still has a momentum and inflexible joints, not only that it can still support Steve's idea so I don't see how this accomplishes anything tbh.
Yeah I have an unpopular opinion in math and it's surprisingly difficult to have a respectful disagreement with someone on it. I'm like why are you getting so upset over something so extremely not important. Math is important but technicalities in mathematic theory isn't worth fighting over.
@@shadowprince4482 haha especially when only 10 other mathematicians worldwide could understand a concept 😂 I'm imagining a mad mathematician explaining that only 10 others understand his equation, half of which agree 😂
I love that this friendly banter has brought more and more accurate representation and example to describe the phenomena through questionning. Thank you, to share this endeavor. It is a great example how to challange our understanding of one thing to make it more accessible for everyone.
@@GjerdanPeterson Every discussion gets high and low. Frustration will happen. It doesn't mean you hate the other party. From what I understand, Madhi and Steve were exchanging a lot of ideas between videos. To learn to explain something in words the other understand is one of the biggest challenge in human history. But when you can, it is the sweetest of victory.
To measure weight, you don't need a scale. You just need a spring holding the chain container. Then measure the displacement of the spring. That gives you a visual readout that works well with filming.
I know I'm late to this, but I was , kinda thinking the same thing, a spring, or a really precise analog scale....film it in slo-mo and grab the measurements as they happen....maybe.
The spring will not necessarily always be in equilibrium, though and you can only 'read off' the weight from the displacement of the spring if you assume that the two forces balance ie the system is in equilibrium. It will take some time for the change in force to propagate through the spring (should be of order the length of the spring divided by the speed of sound of the material) and then the spring will start to oscillate (since the upward force now exceeds the downward force as the suspended length of chain shrinks) and then damp over time to a new equilibrium. So for this type of measurement to work, you need a spring whose characteristic damped period is much much smaller than the time scale on which we want to measure changes in the remaining weight of chain. This implies that we need a very large spring stiffness since the period is inversely related to the stiffness (usually denoted 'k'). But holding all else equal, as you increase the spring stiffness, you make the displacement of the spring from its relaxed length in equilibrium while holding the chain smaller and smaller, meaning we have to measure displacements more and more precisely to get an accurate measurement of the weight. Let's do some order of magnitude calculations. Steve's scales show the chain's full mass is about 2kg. If we want to get a spring that reaches equilibrium on a time scale of 1/1000s like Steve's force gauge, then the the period of the undamped spring better not be bigger than 1/1000s, otherwise the spring will not have time to do even 1 complete oscillation before if has to be back in equilibrium. Therefore, we need a spring of stiffness at least 80,000 N/m. And practically, it will need to be much stiffer because ideally you want the spring to be able to complete many periods, so that it can settle to equilibrium, before you take the next measurement. And for a spring of stiffness 80,000N/m, the displacement from the relaxed length due to the 2kg chain when it is just hanging motionless in the pot will be.... about 0.25mm. The *largest* displacement that we will see in the whole experiment is a quarter of a millimeter. As the chain falls and the suspended weight changes by, say, 100g then that corresponds to a change in the equilibrium displacement of the spring of about 12 microns. To get an accurate reading from this setup, you would need to be able to measure the displacement of the spring with a precision of at least 1 micron, probably less, and that's quite difficult to do.
@@Anytus2007 remember that even the electronic scale functions using mechanical means, it only features electronics to display the number. So you could perhaps connect the wires to an oscilloscope rather than a terrible LCD display to get the most precise reading, a bit like a seismograph. But to have an oscilloscope and know how to rewire it, well youd have to be some sort of electrical engineer! ... I wonder what Mehdi's job might be 🤔
The problem is you need a point of reference, meaning the same thing happening, but without the kickback force, which is pretty much impossible due to the chaotic nature of the chain leaving
Ever heard of inertia and centrifugal force? As the falling mass of chain sliding over the rim is being constantly accelerated by gravity and that the falling mass of chain increases as it is being fed from the resting pile, it pulls each of the resting balls off the chain pile upwards and over the rim with more force than the previous ball which translates to acceleration. So, the next resting ball is yanked upwards with more force than the previous resting ball and is rising faster. Once the velocity of the resting ball, now yanked upwards, passes a threshold it flies upwards clearing the rim of the beaker due to inertia rather than just being dragged over the rim, before gravity and the pull from the falling mass bends it over. In addition to inertia propelling each ball upwards centrifugal force billows out the shape of the turn-over from rising to falling. The resting pile of chain is not pushing the balls up - that is muddy thinking gentlemen and would lead to perpetual motion. Nice try, no banana. Dr. O
Those eyes at 19:30, can't unsee that. I also appreciate the honesty that some of the tests performed were not equal due to the number of changed variables. Demonstrates integrity and an ability to accept criticism in the method.
In my understanding, this is a wave. A static wave. Put the chain on the ground horizontally. Then take one end, raise it up, then put it quickly on the ground. A wave will form and will go up to the end of the chain. The same happens with the chain. It's the acceleration of the gravity that speeds up the chain and it forms a wave. Just, the wave doesn't travel horizontally but stays still while pulling the chain.
"Then take one end, raise it up, then put it quickly on the ground. A wave will form and will go up to the end of the chain" But in that example it is your hand that has provided enough force to lift the chain upwards in the opposite direction of gravity. In the chain fountain the only force acting on the chain is gravity, which is pulling it downwards. Yet despite this, the chain raises up into the air. There must be a force acting on it to make that happen, you can't just say 'it's a wave' without explaining what causes the wave. The individual bars of the ball chain are bouncing off the pile, just like the tail of a skateboard bounces off the ground when a skateboarder does an ollie.
Very convincing! I don't know if I'm hallucinating, but I can also "see" the extra force from the rod, because the rod vibrates when a loop of chain lifts up.
if you know what causality is occurring your brain can chunk your visual input according to the forces you know are present. put another way, if the extra force is real, then it has visible effects, but if it's not real, the things you see must instead be something else. vision is based on inferring explanations for visual behaviors, so the sensation of seeing the forces is likely based on real and reasonable visual chunking, but it wouldn't have allowed you to skip the detailed science because without additional information your vision system wouldn't have been able to select that particular explanation with significant confidence.
The rod definitely is moving- the real question there, and one that would need some real analysis, is whether it's being pushed down by the chain as Steve Mould suggests, or if it's moving up as the weight of the chain is lowering. Or maybe it's just the initial pull on the chain that gets it going?
I just noticed that in a bunched up grouping near the end of the run it starts getting pushed down the whole group of chain is moving down. This completely proves you are correct that there's a force pushing back.
I am curious if you have considered what would happen if you had a chain in which each ball got progressively larger or smaller and how the size of the ball may give additional insight?
You should run an experiment with the pot accelerating upwards and see if that makes the fountain rise faster or higher. Basically, instead of trying to remove the kickback force, you increase it
That stair-step test is the best-designed one yet! Although, I will note that the moderate friction with the flat surface will create a tiny normal force for the minimum-radius chain to push against, and thus, I still think the "spaced out on flat surface" version IS a chain fountain, the fact that the chain reacts so clearly against the stairs demonstrates that this minimum-radius effect must act against a normal force of some type to create the "Mould Effect." Mehdi's "just a minimum radius" explanation focuses on the wrong radius (that of the top of the loop) and neglects that the minimum radius also comes into play at the top of the reservoir. I'm on board now with the lever mechanism... But why does the lever exist? Well, it seems like the peak turn must go to the minimum radius because of the speed of the chain's fall, and the curve between the reservoir and the peak must try to reach a "lowest energy" shape, which will have a large radius. That large radius forces a second minimum radius zone at the top of the reservoir.
This little adversarial competition is awesome, it reminds me of the feuds you read about between renaissance scientists trying to explain the same phenomenon. It's great!!
This whole thing reminds me of nothing more than the actions of a whip - one tries to accelerate the tip of the whip past the sound barrier to make a crack. In doing so, you are using the finite flexibility of the material the whip is made from to impart energy along it in a curve, ending with the (albeit narrower and lighter) end of the whip cracking. The important thing in the above example is the force and flexibility. On the chain, the force is generated by gravity, on the whip it's generated by your body. On the chain, the downward force - once it overcomes the inertia of the chain in the beaker etc - accelerates to it's maximum possible speed. Then, it tries to pull the chain against it's finite flexibility 'curve'. As that happens, the chain rises, just like the wave 'curve' traveling along the whip. Just my 2c.
Without "mould effect" the maximum speed of the chain is unbounded in a frictionless environment. A simple energy calculation shows this (potential energy equals kinetic energy).
16:04 this is how you could test how much force the chain is using to "kick back" by putting the measuring tool on the other side of the pole, you don't have the mass of the chain affecting the readout, therefore you can show/ measure that there is a kickback force and explain it better.
11:43 - Can I suggest an analog gauge. That is - one rough gauge (total weight of chain) and one guage where you put a (still analog) derivator (opamp circuit) so to get the rate of change in real time.
@Andrew : You actually could do it with a "digital" guage, the trick is that the digital form needs to be reading an average, just like the analog guage would display- usually you'll have to build your own to get customized configurations like that.
@@absalomdraconis The digital gauge is perfectly usable as long as it's not a slow LCD which makes you unable to tell when the reading was completed. Averaging is a whole other problem. You can't avoid having a measurement delay with averaging so you need to time-shift the reading back 'a bit' even for analog gauges.
As much as I love seeing Shatner on the edge of space. I would LOVE to see Mehdi and/or Steve on the next trip to the ISS to keep this disagreement going until they are both in agreement!
i always loved listening in on thesis defenses when i was at school. you really get to see what a theory is made of and how good of a scientist the person is presenting it. rule number 1 is you can't take it personally! rule number 2 is rule number 1 is broken constantly by everyone
The chain that rises is gaining energy from somewhere. Is the speed that the chain falls at increasing? In the example where the chain height falls, the actual amplitude of the wave you introduce is also increasing, but because the links are spaced out the chain height falls faster than the amplitude is increasing. You put energy into the system when you introduce the wave which sets up a standing wave with resistance to the remaining pile. The energy of the falling chain supports the wave. If you do not introduce energy the chain would never leave the pile. So you are “kick starting” the system basically. Also, does it work more or less with rope for example? I believe the energy comes form the falling weight and is not dependent on the relative resistance from where the chain meets the pile. A rope experiment would prove or disprove this theory! Actually it is the same principle as water travelling through a tube like a siphon. Only on the chain the tube is a standing wave. When you start the wave you must introduce energy to overcome the initial inertia. The chain mass needs to be greater than the mass of the chain that rises to the edge of the container. The mass also needs to overcome any friction of the chain rubbing on the edge of the container whose resistance and energy eventually sets up its own standing wave (in the event that you didn’t introduce one).
At 11:25 you can see a kink in the chain has to overcome the added inertia due to greater mass of the link, which requires more energy. The kink takes its energy from the wave and the wave height temporarily reduces and then establishes itself again. It is quite simple really. What would be great is if the energy in the wave created over unity! Any way to measure that? Also, it is helpful to think in terms of energy (not force, force being a component of energy) and what the energy must overcome to do what it does. You must be a mechanical engineer not to think in terms of energy and waves?
I'm convinced, but also hope this friendly duel of hypotheses never ends. I was smiling through the whole video. Great science content, Steve and Medhi!
It's amazing to me that this kind of science is still there to be discovered! It's not based on high-tech equipment, or on new theories like quantum mechanics that have only been available recently. It kind of feels like it's the sort of thing that would have been settled in the 17th or 18th centuries by a Hooke or a Cavendish, and yet here we are just solving it now. It makes me wonder what other questions are still out there that are within the reach of the DIY scientist!
Endless boatloads are available to find. Pick a thing you like, get digging. I assure you theres lots of unanswered seemingly basic things to figure out.
When was this kind of metal chain made though? These metal chains are hard to make. I wonder if that would explain it. That said I agree, I believe that if we got given a book of all physical rules, we'd still have centuries of physics left. Both in terms of finding weird consequences like this and also finding useful abstractions for larger scale effects.
Hi Steve, to measure the reaction force on a horizontal plane (9:30), you could try to use a pressure sensitive film like the "Fujifilm Prescale". If the forces pushing against the plate to lift the chain up are high enough, you should be able to observe the forces on the sheet.
This back and forth between Steve and Medhi is like one of those infinite sums that neither diverges nor converges. I think we need Mathologer to help us out.
This is the kind of scientific dispute which I never thought I'd get to witness live on youtube. Excellent work to both yourself and Mehdi for keeping it all friendly and civil, love to see it
This reminds of how large boats utilize their anchors. As the anchor is lowered and the chain released increases the weight of the total load, a braking system has to be used along with a cooling system to prevent a total failure due to heat from friction...
Well, I think the simplest explanation would be this: If you try different types of chain that have different flexion angles, it will cause the fountain to be lower or higher depends on the bending ability of the chain. If you just take an ordinary chain without stiffening ribs, it will just drop down like you expect.
I think the amount of flex in the chain is a factor in the shape of the 'wave', but not what causes the wave to rise in the first place. The wave will still happen no matter how flexible it is. I think it is friction that causes the wave to propagate, as the chain changes direction it slows down because of friction, but the mass of chain behind it is still moving faster, pushing the apex higher. As the chain falls from the apex, it straightens, reducing friction and it's speed increases again. Which is why the wave doesn't keep getting taller and taller, but settles at a certain height.
This is the modern version of Newton, et. al. sending letters to each other, especially when the two correspondents disagree with what is happening in an experiment or calculation.
"I’ve yet to see any problem, however complicated, which when you looked at it the right way didn’t become still more complicated.” - Poul Anderson it's the equivalent of being mesmerised by the most chaotic movements in a lava lamp.
Observe what happens at 20:48 to 20:49, in that transition the remaining chain hanging from the bar moves down as if it is trying to start flowing in the opposite direction and then is pulled up by the momentum of the chain travelling upwards. If we compare the fountain to a mass spinning in a horizontal plain tied with a string pulling up on an equal mass vertically we see that as the spinning mass accelerates it pulls the vertical mass up but as it enters a larger orbit the vertical mass stays stationary as it slows down the vertical mass drops and as the spinning mass enters a small orbit the vertical mass becomes stationary again. If we pull down on the vertical mass the spinning mass accelerates or rather spins faster as it enters a closer orbit to the center of rotation trying to maintain its energy. In the falling chain fountain once the chain hits maximum velocity in the downward direction it no longer tries to maintain its energy by moving to a larger arch, also as it accelerates in a downward direction it also tries to rotate faster and enter a larger arch (orbit) but as it is not tethered and passing into its arch of rotation at different angles, it flaps around like a fish out of water. If there is any downward force being applied to the jar it is falling out of it is caused by the inconsistent location of its departure in combination with the flapping action. Ever drop a slinky down the stairs?
The more organized the beads are the easier they are to accelerate. Any disorganization leads to a dampening affect. If both of you use the same vessel and organize the beads so the direction they want to travel is only linear(similar to a fishing spinning reel) it will minimize variables. I would recommend spooling them in a vessel that's diameter is the maximum diameter of the chains smallest possible diameter. I feel every bead is accelerated differently since the direction is always changing it will be dampened. Just a suggestion, no need to over complicate it...lol good luck.
Brilliant! Often when looking at problems we have different views which seem opposites at first, maybe that's the case here. On one hand you have the inertia of the chain going over the lip of the container or simply continue it's path, on the other hand we need to have a supporting force in the container so that the chain can stand up. The disagreement is sort of a communication problem, when you say that there is an "extra force" it sounds like something absurd like if the container or pile was doing something more than reacting. That lever explanation seems a bit flawed, but yeah, the bending resistance probably helps to create the raised loop.
Right now, (I’m comfortable saying) you have the most uniquely “educational” channel. The video discussion/demonstration regarding a water computer was a completely new topic for me. Personally, I think it would be fantastic to learn more on the topic of “water” in all (and each) of its various states….and studies involving its resourceful uses. Thank you Steve :-)
You guys just need to collab TOGETHER for a week. And in the end, the winner has to buy the loser dinner; TOGETHER. This way it will be a beautiful end no matter what. P.S. Make sure you include a photo of the dinner bill.
Here's an experimental setup that may allow for a scale reading: set up a large plate on top of the force sensor. Place the vessel containing the chain on the plate such that the chain exiting the vessel also lands on the plate. Aside from variations caused by vibrations and during the initial non-steady state acceleration, you should be able to average over the entire run to get a pretty good value for the weight - and therefore extra force. Compare this averaged weight to the initial weight of the vessel and chain (less the amount in the air during the motion). Not sure if this requires unattainable precision/accuracy, but it does get around the constantly changing scale reading.
4:57 You can see though that Mehdi is using a slightly different camera effect, as he moves his head right and left and the camera is not stuck to his head.
With the rod setup, has anyone put it on a bearing? The downward force on the rim of the rod isn't just offset by the cantilever it's also offset by torque.
GREAT suggestion! I think, just after the 5 seconds since I read your comment, that perhaps that would increase the speed &/or height of the "peak" of the up-swinging-then-falling chain ⛓, as the forward-most chain length's upward force would encounter less friction, thereby allowing the upper "fountain" section to be unraveling the chain quicker, not slower [or without the upward fountain manifesting] as in Steve's last simulation clip (where he removes the pole) because the pole is still there to 'push' against. The ball bearings on the pole would just allow it to run quicker, and as I predict, increase the height of the fountain.
Thanks for all the suggestions that went into this video! What do you think? Convincing?
You can also discuss this video on REDDIT: stvmld.com/n26_w4an
And can I just point out this brilliant video that came out the day before this one and has a lot in common: th-cam.com/video/I31GfljDEWA/w-d-xo.html
The sponsor is Curiosity Stream: Get a whole year for just $14.99 curiositystream.com/stevemould
Have to watch the video to know
There is another thing to consider may be,
That the chain colecting cylinder
From 6th min the left one vedio collects the chain at one stop only making the radius of a chain collecting at a given time increasing
Where as in another case the right case the chain is collecting overall the cylinder so, the radius of chain collecting at a given time is constant
And so, at left vedio case peak may constant and in right case peak is reciding .
Never any doubt (after the last one and a good think)
Nice new collection of experiments, though!
If this is not convincing, nothing will be.
The inertia from the rising chain is what’s doing it. You are tossing the links in the air. There is clearly a minimum velocity required for enough energy to clear the rim. I first thought it was the internal levering of the strand of chain at first also.
i think you neglect the centrifugal force playing in the moving loops (because there are smaller ones before the top one), whipping the chain around.
The chain has a substantial speed in the loops.
This proves what YT needs is more adversarial collaborations. Great work! I was convinced by your last video but now I’m even more convinced.
It has been a WW3.
Okay but explain this… th-cam.com/video/gGtO2zPQkec/w-d-xo.html
2
This is what science used to be and I'm very much here for it. It's like watching Einstein debate Bohr.
Friendly science battles! We all win with the knowledge gained!
19:26 makes me believe you are absolutely right! 😄 ok let me go do my own electrical analysis and see what I come with... great explanations as usual!
cant wait for your video
Go go go! (((:
Not gonna lie, I think he got you on this one. I do beliieve your hypothesis does contribute in the stability of the fountain tho.
I wonder how long this is going to be.
@@good_guy_SG As I said: Mehdi vs Mould live from ISS
after watching this series, I have serious doubts in my critical thinking skills. I can be convinced of anything with a good enough orator.
Same here! I’m glad those videos expose my critical judgment that way, cause I’ll get stronger from here!
Nice pfp
Maybe they just both present compelling arguments? No need to doubt yourself. They're both giving evidence for their assertions and they're good arguments
If true that's an incredibly valuable insight for your own life, congrats! :)
I think Medhi's first video very legitimately pointed out real flaws in the experimental evidence Steve provided. The experiments really got refined a lot over these videos, but unfortunately for Medhi, the experiments still agree with Steve.
But it was too easy to go from "experiments were flawed" to "theory was flawed".
I mean these videos are literally a good lesson in why peer review is an important part of turning experimentation into knowledge
this is not even remotely how peer review works
@@samb443 But it is how competition works. Capitalism, baby!
Except for when the peers are corrupt with ideology
@@AR15andGOD That's why anything significant is peer reviewed by many.
Why would you say ''I mean''?
The real Mould effect was the adversarial collaborations we made along the way.
The real adversarial feeling we made along the way, was Mould
@@DarrenDignam The Russians were doing this long before Mould.
nothing wraps up a good adversarial collaboration quite like the moral behind it all
The real The Russians were doing this long before Mould. is the Real adversarial feelings we made along the way, was Mould we made along the way
I have a real mold effect around the bathtub. 😆
Mehdi is right about one thing: Steve's blue eyes and soothing voice are mesmerizing.
19:31
Yup. He could stop a prison rape just by talking.
Yes, I think it all makes sense now. O.O
Don't forget the unibrow
And Medhi's shocking personality is riveting
This all was the purest definition of “I respectfully disagree, …” Except, in Mehdi’s case it’s “I respectfully disagree, despite your mesmerizing blue eyes and soothing voice…”
But he has more followers!
😶 u a kid?
@@PerErikKarlsson follower count is not relevant to anything other then adcents payout.
@@jaydunbar7538 guess you haven't seen Electrobooms first video on the chain fountain.
@@jaydunbar7538 Medhi's joked about it.
This is a great demonstration of why disagreements are good. Sure, one side is wrong, but it drives the other side to go into far greater detail about things and in the end you're left with a much better understanding of the problem. It's beneficial for everyone.
It's clear to me that chains are actually just sleeping snakes, and when they start falling they panic and arch up
This is the right answer
Claim your 10,000 cents my guy, you've made it
"It's clear to me that" is the best way to start the results section of a scientific paper.
yes
Yeah, obviously.
I love how Steve is becoming an expert and spending hundreds of hours studying pouring a chain out of a beaker.
I mean, the effect is named after him
this is what it means to science
While we were watching youtube videos, he was studying "the chain"...
@@IRNoahBody they're both doing the math, just usually off screen as none of it is necessary for the videos.
@@professorfukyu744 its crazy to think that professional math people wouldnt be....doing the math
Perhaps the gemiest of gems on TH-cam. Steve vs Mehdi. Great followup Steve.
I love that all you guys watch as well. I'm sure it means a lot to these guys. By you guys I mean fellow creators
The individual beads on the chain would experience constant acceleration during the event from start to finish. The bead centre of gravity stays the same while the overall systems centre of gravity changes. This leads to a whipping effect.
If you hold the bottom of that chain and use a whipping motion upwards the beads would rise proportional to the energy added from the system. It would create an arch exactly the same until all the beads left the pot
I wish this doesn't stop and we have an infinite chain of proofs and disproofs
Now we need a collab between you and the thought emporium!
Former industrial rope guy here. Watching this series reminds me of observations made at a film set that involved passing thick rubber coated power cables down a cliff. Care had to be exercised once a certain amount of cable was payed out as it would quickly become, and I’m being extremely tame in my description: “self lowering”.
I love how Steve amplified the hypnotic effect of his baby blue eyes at the end as to secure his hold over Mehdi's mind. Maximum persuasion. 😂
Yeah… we all understood it, ur not special
@@henreereeman8529 Ooh, adversarial. I see what you did there. 😛
Has the same effect on most people I think! :D
SPEECH 100
Honestly he seemed pretty honest and credible up until that point. But manipulation tactics should never be used in arguments. Now it seems like he cares slightly more about winning than getting it right - getting it right is just a crucial part of the persuasion. And you shouldn't trust people with loaded motivations on any sort of thing based on truth-seeking, should you?
Is it bad that I want ElectroBOOM to find another hole in your explanation?
Not because I really care that much about whose right (I just wanna know what really going on and I don't care who finds it first), but because this playful back and forth is one of the most fun YT collabs I've seen in years.
@@IRNoahBody I have a huge ass book labeled "fundamentals of physics" maybe steve can put it to good use.
@@IRNoahBody didn't he go through the force diagrams in one of the previous videos
edit: ah nevermind I see what you meant
*who's
@@IRNoahBody sorry, can't make sense of what you wrote in the last part, but I would take the conclusions of a computational physics program over an enraged guy with a little whiteboard to calculate extremely complicated real life physics.
Side note: 3D CGI effects for movies/animations where cloth and hair is flowing in the wind, and even mind-blowing realistic fluid dynamics like a flood rushing through a city is all generated by a computer physics engine that can develop and render a realistic outcome all on its own, and could never be achieved by an army of humans without the aid of the program. It also wouldn't be possible to achieve by a guy with a pen and whiteboard either, no matter how enraged he got.
for me that is the simple answer.
the falling part of the chain speeds up generating more chain tension than the rising part. This is implied by the fact that the chain fountain is rising because the greater tension (force) causes the chain curvature to straighten more quickly on the more stretched side, causing the curvature to move upwards against gravity.
In short - the side that is pulled more eagerly and faster straightens, which causes the curvature to shift in the opposite direction to the pulled side.
This is one of the best examples of science being made, and why peer review is so important.
This has nothing to do with peer-review though. The reviewer is not conducting their own experiments. This shows though how productive healthy competition can be.
Peer review is the evaluation of work by one or more people with similar competancies. It’s true academic peer review for a scientific journal wouldn’t do a replication study, But the disputes come from reviewing each other’s work and criticizing. They are playing to more than just each other, they are also playing to an audience, an audience who grew up on myth busters and bill nye, not rigor. They demo. That’s what these videos are are, science explanation combined with visual demos that function as experiments.
The criticism of experimental technique and challenging unproven conclusions, is key to peer review. The shown visual experimentation is for an audiance who doesn’t grasp the concepts well. As the myth busters showed, visual science sells. But gussy up the videos, supplement to visual demos with a lot more rigor, and the actual criticisms lobbied back and forth are review of the of the works each put out. It’s peer review, it’s just not academic peer review.
@@DeadSpatula The reviewers have competence, but not necessarily in the same area. They just look for obvious flaws or faults.
@@muuubiee my point was that the back and forth we see here is not what is meant when scientists talk "peer review". This is related, more akin to replication.
This is such an epic nerd feud. I hope it never ends.
Basically how AI got so good. Science is all about blind agreement now and that will get us nowhere. Just like how the Chinese closed themselves off and ended up being owned later by a civilization that came up with new ways of doing things
If you hope it never ends, then you can't be very invested in the science of it - and that means you're not a nerd!
@@aceman0000099 you mean when they die? Obviously the feud has to end eventually.
And I’m certainly not a nerd. You are correct.
@@darrenstettner5381 besides, it's over in case you didn't know
who needs stupid logan paul boxing matches when you can have scientific 200iq debates
Idk what is wrong with me but its like the 5th video about a metal chain falling down and somehow i get more excited with each one XD, ty for keeping my brain off of my engineering degree
It’s the joy of science!
@@minerharry nah it's probably the drama that gets things exciting for him...
Absolutely nothing wrong. The drama of the twists and turns of points and counter-points as we swirl around the solution to an interesting question is quite reasonably very exciting. A simple "metal chain falling down" may not be all that interesting, but this exploration of a curious phenomena and debate around it are far more nuanced and complex than merely watching a piece of metal get dropped : )
A few hundred years ago this whole debate would have been happening in writing. A joyful innovation.
On of the best commentaries
That is interesting, isn't it!
It would likely have been viewed as black magic or witchcraft and ended with the presenter being strapped in the ducking stool or rolled down hill in a spiked barrel....heretics😂
Why does this coment have the energy of a vampire who is still amazed by the internet and long distance communication in general?
You mean like 30 years ago right?
"I'll go into the derivation later..."
Later: "I won't go into the derivation".
Ah, yes, Proof by Deferral and Avoidance, classic
[Mehdi voice, jutting camera angles]
You didn't go into the derivation, STEVE.
If you have a million subscribers, you don't give a shit about things like that.
@@hugofontes5708 Then it's left as an exercise for the reader.
just like my college professors
1:30 in slow motion I believe you can actually see this happening when it hits the longer chain link and you can visually see the chain react more aggressively because of the sudden change in overall stiffness
The best thing about this collab is that it shows the "normal" person how to discuss a scientific topic, and how easily you can become preoccupied towards either side, if they talk convincing enough. Thanks for being a good sport and an amazing role model!
They call them laymen
Nerd ;p
@@xAxMxWx 8:26
You could easily align the footage with a USB force gauge by tapping the top of the breaker the chain is in before doing the fountain. Just align the spike in the graph record with the tap on camera. Same theory as clapping to align the audio with the video when recording from a standalone audio source.
Very nice!
You should also tap it again at the end, because the sampling rate is going to differ from the camera's frame rate and you need two points to scale their time axes properly.
I'd be curious to see if there'd be a (small) spike in the (graph of the) reading when the loop passes over the rod in the setup shown at 15:50
Edit: watching through 16:00 at .25 speed, the loop passing over the bar appears to be when the "additional" force is applied. I also really enjoy how clearly the pronunciation of "additional" comes across as "a-dish'-nal" (vs "a-di-sho-nal", etc.)
This might not work, because the scale display operates in "cycles". You may create the spike at the end of a cycle and measure a small delay, when if the spike happened at the beginning of the cycle, you'd have a longer delay. This might be able to be overcome, but something to think about
Why not use an Analog force gage? Wouldn't that do the trick?
The essence of peer review is adversarial. My job as a reviewer of a paper for a journal is to try to find the flaws in the logic, design, analysis, conclusions, etc. I then report my evaluation. While not all reviewers are this way, I try to write my reports in a kind manner, but it can't help but come out with an adversarial tone because that's the nature of the peer review beast.
My reply: and what do you think? Just curious.
Once the chain is moving fast enough, the rigidity in the chain is your lever, and that rigidity gives the large downward section of chain the mechanical advantage to lift the portion that is at rest, up. The “lever mechanism” IS the rigidity of the chain. No “kick up” from the container needed. When the mechanical advantage is large enough to overcome the weight of chain on the “up-side” or “at-rest-side,” the fulcrum can move up. The only force needed is from the tension in the chain on the “down-moving-side.” If the container were to be “kicking up,” the chain could start moving on its own. (Think of the rigidity in the chain like a bent 2x4 that is flinging the chain up from the fulcrum… the place where the chain is bent to some critical point (the fulcrum) seems to “spring up” the upward-moving-side because it is already moving upwards, and it is a shorter length, and is therefore lighter in mass relative to the downward-moving-chain.)
@Jack @Steve Mould The chain doesn't spring up on its own because there's no energy change in the system at that point. The energy ultimately comes from the falling chain (conversion from potential to kinetic energy), but the dynamics of it transfers to the just rising link in a non-intuitive manner. This becomes a limit to the speed of the chain and the height of the fountain when the force pulling down balances the resisting force of the rising chain. The reason for the kick up is the pull down which is converting potential energy to kinetic energy. Note that the 'fountain' effect increases from nothing as the speed of the chain ramps up. The speed of the chain will create a proportionate jerk on the end of the piece of chain entering the rising portion. Because of momentum on the entire link, it tends to stay stationary which means the link 'sees' the pull on one end as tending to rotate the link, meaning the other end has to push downward. That downward push then pushes the entire link up. That push up is proportionate to the change in momentum from zero to the speed of the pull up by the chain, and is added to the speed already set as an acceleration. As the speed increases the fountain rises to a limit because there is added energy.
I think you're doing it the right way. Some people can take constructive criticism, and others cannot.
@@lagautmd if there was no change in energy at the fulcrum, it could not rise. the fountain effect begins as soon as part of the chain is bent to its maximum. The downward force increases as the chain moves faster. The “downward-moving-length” is longer and heavier than the “upward-moving-length.” The point of the chain that is bent to maximum is the fulcrum and the chain links are like a teeter-totters. “Non-rigid teeter totters” ….. which can load like a spring. The unbalanced force is what gives the “spring” of the fulcrum it’s mechanical advantage to fling up the next link.
I think much of what you said is in agreement with me. The fulcrum can rise because of the loading and unloading of the “springiness” of the rigidity in the chain. The extra force or mechanical advantage does not come from the table, but from the unbalanced forces in the chain. The rigidity in the chain is the lever, and that loads like a bent board.
No rigidity… no fountain.
This kind of reactionary videos; polite and honest are awesome. There should be more poeple like you both in the world!
Yeah, not the priestly arrogance of mainstream science. All we know is that we know nothing. Through Socratic argument (which got Socrates killed) can we discover truth.
Assuming both parties are being genuine, any scientific discussion should be pretty easy to keep civil. It's not about opinions or ideals about how things ought to be, it's about observations and understanding how and why things are.
@@generalcodsworth4417 Its all about that assumption and the scientific part. Guess I watch to much social media crap ;)
"Why didn't you mention the simulation" absolutely slayed me
Do not trust any simulation that you have not created yourself according to your own ideas.
because someone created a 100% accurate simulation of the universe on their computer to simulate the chains going brrrr, and it isn't just some random project he did in 1 hour tops
And the beautiful blue eyes 🤣
I'm sensing a Medhisturbance in the force!
@@AdrianOkay it was the way he said it, not really what he was saying... but I get you're point and agree
@@slickfast yeah i was replying to eld0r but forgot to put the tag
I love this debate playing out in the open. Too many people have no clue that this is how science really happens. On the other hand, I think some in the science community could take a lesson from the spirit of friendly debate being displayed here. Too often deep acrimony develops from disagreements. We should all be focused on getting the best answer, even if it means, in the end, that we were not correct in our original hypothesis. Honest open debate with supporting experimental evidence helps science (and in turn, society), character attacks do nothing but show the real character of the one doing the attacking.
Physicists at least are way less petty/cruel than paleontologists.
@@SamAronow
What do paleontologists get up too? Surely they can bond over beating up creationists in the car park.
@@pseudonymousbeing987 Paleontology kinda incorporates both science and exploration, the latter of which brings with it things like bragging rights and dick-waving that leads to lifelong blood feuds and libelous public spats. Look up Richard Owen.
Now imagine if TH-cam decided that this chain fountain issue was important to public safety so they banned Electroboom's videos, as well as anyone else's video who disagrees with the people TH-cam declares the "experts" on the topic.
This is what is happening with discussions about COVID-19 and the vaccine. All discussion has to take place behind closed doors and isn't allowed to be transparent because TH-cam (as well as Facebook and others) have declared themselves the arbiters of truth and have decided for us which experts we shall exclusively listen to.
@@LowJSamuel yeah, no.
next episode: Zero gravity chain fountain test proves me right (I'M IN SPAAAACEE)
I don't understand why this doesn't have more upvotes. Although if the put a beaker through one of the windows on the ISS' cupola I think Steve and Medhi had better change addresses...
@@Rockancrime this is not reddit, upvotes are likes on youtube
@@asepsolihin5199 Upvotes, Likes, Internet points... You clearly understood the heuristic.
Who are you.... Tom Scott?
It would take forever to conduct this experiment in zero gravity.
I first experienced this when I was very very young taking out Christmas decorations. We kept a long thread of red, wooden cranberries to wrap around the tree and one year I was unpacking it and WHOOSH the chain came raveling out of the bag making an arc. I must've been 6 or 7 so 2002/03. Very cool to see people talking about it. I assumed it was already studied!
This interaction between the two of you is a perfect example of why peer review is such a powerful tool in scientific exploration. Everyone has bias; it is unavoidable. And sometimes people just miss things. Great job.
sometimes the bias is just that you aren't explaining it very well, because you are biased in that you already understand what you are trying to explain. That is why they say you learn a lot when you have to teach something.
@@thecookiemaker I agree 100%. I often solve my own problems when I explain the situation to a co-worker.
And this is why people that are anti-science bother me so much.
Man, these videos with the "friendly fight" are amazing. I've found your explanation more convincing from the start, but seeing Mehdi force you to really step up and prove it - while you do the same to those who think his explanation is more convincing - is just a lot of fun!
Science is supposed to be adversarial. That's what peer reviewed is supposed to mean. Most unis and r&d have biased sponsors that want a result and will pull funding if thier predetermined solution isn't "found"
Real science is constantly telling everyone they're wrong while they all come at you full force to poke holes in your thesis.
19:05 It's fascinating how you can see his eyes rotating to compensate for the head movement.
Why'd you have to say that? :(
@@Rafaelinux Because Steve Mould has done a video about eye rotation.
@@Rafaelinux and what is your problem with them saying that?
Perfect avatar for this comment
Bear in mind (a) human eyes do that normally, which you can check with a mirror, and (b) he's holding the camera he's rotating, so his body knows which way things will turn next.
Scientists and those prone to scientific investigation used to do this via articles and journals. YT is a great medium and we definitely need more of this.
"It all makes sense" that too with big blue eyes are convincing enough for me
The only way to prove this once and for all is for Steve to explain things from the top while wearing brown contact lenses so we're not mesmerized by this blue eyes
Agreed
the soothing voice would stay that way though! we're gonna need a TTS program to be talking for him to nullify it
@@verkhvo or perhaps a friend of his with a less soothing voice to read a script on his behalf?
@@michaelsorensen7567 i'd imagine all of his friends have equally magical voices. it has to be a silly robot for us to be completely sure
@@verkhvo just some dude on the road
This collaboration is like an inside look into the scientific method. I love the deep look into peer review. I would very much like to seem more of this amazing content.
Amazing set of videos here!! Really loved it !! Hope this kind of healthy competitiveness keeps on going. Thanks so much for the hard work👏🏻👏🏻👏🏻
To measure the force, I would recommend strain gauges, a Wheatstone bridge, and a USB multimeter. After you get past the annoyance of calibrating the strain gauges, you would have an accurate feed of force vs. time. (This is what early aerospace engineers did to get similarly accurate measurements of forces on wind-tunnel models) You could do it with well under $100 of instruments. Can't help you with the tedium of counting the chain links and time syncing the data to the video, though.
Probably tapping on the force gauge while video recording it will be a good sync point.
I also found that if you have a very high impedence volt meter (~100 Mega ohms, like the adc of an Arduino uno) use can use a piezo speaker as a very sensitive force gauge. You might want to divide the voltage with ceramic capicitors in series. Also note that they technically produce voltage when the drum deforms into a bowl, not when it is squished. The crystal is grown radially.
I think you meant “ten thousand American cents” :D
LOL this comment perfectly enapsulates just how insane this has all gotten.. and I absolutely love it.
Edit: btw, very engineer-y of you to considering how he can do your suggestion while still within the budget (well, the budget assuming he wins. And I realize that makes no sense for a monetized youtube video from a professional science educator, but you know what I mean!)
🔝
Strain gauges are a pain in the arse. I've used them in a full bridge before and got crazy drifts over temperature and still little sensitivity to the direction of interest. Getting pre-built gauges is the way to go.
You two have basically just provided the justification for peer reviewed journals ;)
Spot on!
If only there were similar debate on news topics instead of censorship of opposing views.
Unfortunately that's not how peer reviewing actually ends up working in practice. Peer reviewing almost never involves recreating the experiments to validate the data or other relevant experiments to attempt falsifying the original, only that everything looks to have been performed and recorded correctly. It's less duplication for scientific rigour, and more editorial proofreading for science writing.
It's still important for the validity and reputation of a journal, but it's not nearly as rigorous as the vast majority of people believe it to be. Especially when you get into fields like sociology where the majority of published research can't be duplicated.
@@Meton2526 Alas, yes. And until recently, it was very uncommon to provide full data sets or full code with your papers. So in a sense, it was really just proof reading.
Real world people in real world companies trying to follow along eg chemistry papers typically expect most stuff not to work. See NileRed's channel for a taste of that.
And chemistry is still one of the harder sciences.
These are hypothesis and hypothesis have nothing to do with journals
Damn, I love watching competitions between scientists. Especially if both have very reasonable arguments, but both end up wrong and open up more trains of thought
One could argue that the half-circle radius as given by the tension and velocity of the chain is at an optimum. In one of the clips he makes a motion as if with a whip. Does the tip of the chain react to force from the hand holding the jar before it hits the ground?
@@Garganzuul we're too concerned about if we can argue instead of wether we should.
It's so fun watching those arguments between scientists it's like I'm back in 1800s
I've literally changed sides every single time, I'm just enjoying the show at this point.
And then you find out that it's not possible for everybody to be right but is 100% possible for everybody to be wrong.
@@E-Box
_the real chain fountain is the friends we made along the way_
Should make you question the videos you watch elsewhere more! That said it could be a good thing, maybe you don't form opinions into unbreakable beliefs !
Not this time. He lost at 14:58. "Inertia increases" makes no sense whatsoever.
@@frosty1433 If you say so man 🤷♂ in case it wasn't clear I'm an utter physics layman.
The blue eyes section at the end of the video had both me scared shitless and tearing up in laughter.
lmao I love this back and forth series, I sincerely hope this never ever ends
True
I think it may have done with how convincing this was. But you know how crazy Medhi is, who knows his reaction 😂
I can reassure you that's going to happen, we still have flatearthers today...
Hopefully not over the same topic, but other "Theories".
The additional force?
Easy - acceleration!
The falling chain is transferring its kinetic force into the static chain that has limits to his flexibility, attempting to pull it directly toward itself. But, being a flexible length it wants to follow the force that is already being applied - vertical acceleration. Once the vertical acceleration is overcome by the downward force of the falling chain it is pulled - in as much as its flexibility allows - back downward.
Just like you'll see a bow in a whip as it is extending toward its terminal length. Since there is nothing at the end of that length all of the energy is concentrated into the tip, allowing it to break the sound barrier. The same applies to animals shaking out their fur. The abrupt change in direction over a short flexible length causes a snap which breaks the surface tension of the water adhering to their coat.
Since the chain does not have that terminator, all of the acceleration energy builds in the curve until the very end of the chain (which, by the way, you never let us hear) which probably makes a pretty sharp little crack as it reaches the top of the arc - though the mass of the chain likely limits that considerably.
This is essentially what I think. They don't seem to be factoring in the accelerating force of gravity. And it's cool to me that the phenomenon expresses itself as a sine wave form. Not sure about your noise at the end theory, because I believe a whip's crack is caused by the tip breaking the sound barrier, isn't it?
When this is finally settled, I'm hoping the pair of you formally publish your findings in a journal
Yes, and perhaps it shall be named The Mould-Mehdi effect
@@fureversalty I wonder if Mehdi would be happy that he's included or upset that he's second 😆
I have an idea. What if instead of the wide mouth beaker, you piled up the chain in a long acrylic tube? Say a 12-25mm diameter tube. This would allow you to have a really long(deep) static chain, and see if the fountain still rises away from non moving pile. Its similar to your floor idea, but you get to see the same effect as the beaker setup.
This would be interesting to see, if the tube was longer than that meter high maximum he established in this video. Will there be no fountain as the chain passes over the edge of the tube?
ohhhh like a graduated cylinder?
Well he did have a long tube(50-60cm) in height for the first experiment th-cam.com/video/qTLR7FwXUU4/w-d-xo.html at 6:10 , But I guess it needs to be even longer like 1.5m
That seems overly complicated... maybe do it with tube that's 1/2 to 1 inch diameter.
Thing is it wouldn't disprove mehdi because all he believes is that the momentum of the chain combined with its inflexibility at the joints causes the loop. No reactionary forces required. A deep tube still has a momentum and inflexible joints, not only that it can still support Steve's idea so I don't see how this accomplishes anything tbh.
The world needs more friendly, respectful adversarial science.
Yes! Yes it does!
Yup
Yeah I have an unpopular opinion in math and it's surprisingly difficult to have a respectful disagreement with someone on it. I'm like why are you getting so upset over something so extremely not important. Math is important but technicalities in mathematic theory isn't worth fighting over.
@@shadowprince4482 haha especially when only 10 other mathematicians worldwide could understand a concept 😂
I'm imagining a mad mathematician explaining that only 10 others understand his equation, half of which agree 😂
Constructive disagrrement. Politics as well. ...Just everything really.
The friendly competitiveness and poking back and forth is great! Thanks for the fun videos!
I love that this friendly banter has brought more and more accurate representation and example to describe the phenomena through questionning. Thank you, to share this endeavor. It is a great example how to challange our understanding of one thing to make it more accessible for everyone.
This one seemed less friendly and more passive aggressive tbh, it got friendly at the end tho.
@@GjerdanPeterson Every discussion gets high and low. Frustration will happen. It doesn't mean you hate the other party. From what I understand, Madhi and Steve were exchanging a lot of ideas between videos. To learn to explain something in words the other understand is one of the biggest challenge in human history. But when you can, it is the sweetest of victory.
"We're in the endgame now."
Wow, that step setup was pretty convincing.
Edit: wow, the whole thing was convincing. Isn't science awesome?
To measure weight, you don't need a scale. You just need a spring holding the chain container. Then measure the displacement of the spring. That gives you a visual readout that works well with filming.
I know I'm late to this, but I was , kinda thinking the same thing, a spring, or a really precise analog scale....film it in slo-mo and grab the measurements as they happen....maybe.
The spring will not necessarily always be in equilibrium, though and you can only 'read off' the weight from the displacement of the spring if you assume that the two forces balance ie the system is in equilibrium. It will take some time for the change in force to propagate through the spring (should be of order the length of the spring divided by the speed of sound of the material) and then the spring will start to oscillate (since the upward force now exceeds the downward force as the suspended length of chain shrinks) and then damp over time to a new equilibrium.
So for this type of measurement to work, you need a spring whose characteristic damped period is much much smaller than the time scale on which we want to measure changes in the remaining weight of chain. This implies that we need a very large spring stiffness since the period is inversely related to the stiffness (usually denoted 'k'). But holding all else equal, as you increase the spring stiffness, you make the displacement of the spring from its relaxed length in equilibrium while holding the chain smaller and smaller, meaning we have to measure displacements more and more precisely to get an accurate measurement of the weight.
Let's do some order of magnitude calculations. Steve's scales show the chain's full mass is about 2kg. If we want to get a spring that reaches equilibrium on a time scale of 1/1000s like Steve's force gauge, then the the period of the undamped spring better not be bigger than 1/1000s, otherwise the spring will not have time to do even 1 complete oscillation before if has to be back in equilibrium. Therefore, we need a spring of stiffness at least 80,000 N/m. And practically, it will need to be much stiffer because ideally you want the spring to be able to complete many periods, so that it can settle to equilibrium, before you take the next measurement. And for a spring of stiffness 80,000N/m, the displacement from the relaxed length due to the 2kg chain when it is just hanging motionless in the pot will be.... about 0.25mm. The *largest* displacement that we will see in the whole experiment is a quarter of a millimeter. As the chain falls and the suspended weight changes by, say, 100g then that corresponds to a change in the equilibrium displacement of the spring of about 12 microns. To get an accurate reading from this setup, you would need to be able to measure the displacement of the spring with a precision of at least 1 micron, probably less, and that's quite difficult to do.
@@Anytus2007 remember that even the electronic scale functions using mechanical means, it only features electronics to display the number. So you could perhaps connect the wires to an oscilloscope rather than a terrible LCD display to get the most precise reading, a bit like a seismograph. But to have an oscilloscope and know how to rewire it, well youd have to be some sort of electrical engineer! ... I wonder what Mehdi's job might be 🤔
The problem is you need a point of reference, meaning the same thing happening, but without the kickback force, which is pretty much impossible due to the chaotic nature of the chain leaving
@@aceman0000099 time for alphaphoenix to bring in his oscilloscope?
Ever heard of inertia and centrifugal force? As the falling mass of chain sliding over the rim is being constantly accelerated by gravity and that the falling mass of chain increases as it is being fed from the resting pile, it pulls each of the resting balls off the chain pile upwards and over the rim with more force than the previous ball which translates to acceleration. So, the next resting ball is yanked upwards with more force than the previous resting ball and is rising faster. Once the velocity of the resting ball, now yanked upwards, passes a threshold it flies upwards clearing the rim of the beaker due to inertia rather than just being dragged over the rim, before gravity and the pull from the falling mass bends it over. In addition to inertia propelling each ball upwards centrifugal force billows out the shape of the turn-over from rising to falling.
The resting pile of chain is not pushing the balls up - that is muddy thinking gentlemen and would lead to perpetual motion. Nice try, no banana.
Dr. O
I believe you are correct. The chain follows the same path as a water fountain for the same reason.
Those eyes at 19:30, can't unsee that.
I also appreciate the honesty that some of the tests performed were not equal due to the number of changed variables. Demonstrates integrity and an ability to accept criticism in the method.
I really didn't like the bug eyed look. Just creepy to me.
This is probably the sweestest argument between two people on a scientific discovery. 😂
Interesting, you added this to a playlist so I can watch it while still "unlisted"! Cool
Remove your comment, keep this a secret
Bruh 10 hours ago
How is this 10 hr old?!?!
@@krishvasa7644 He explained in the comment itself.
@@du42bz yeah
In my understanding, this is a wave. A static wave. Put the chain on the ground horizontally. Then take one end, raise it up, then put it quickly on the ground. A wave will form and will go up to the end of the chain. The same happens with the chain. It's the acceleration of the gravity that speeds up the chain and it forms a wave. Just, the wave doesn't travel horizontally but stays still while pulling the chain.
"Then take one end, raise it up, then put it quickly on the ground. A wave will form and will go up to the end of the chain"
But in that example it is your hand that has provided enough force to lift the chain upwards in the opposite direction of gravity.
In the chain fountain the only force acting on the chain is gravity, which is pulling it downwards. Yet despite this, the chain raises up into the air. There must be a force acting on it to make that happen, you can't just say 'it's a wave' without explaining what causes the wave. The individual bars of the ball chain are bouncing off the pile, just like the tail of a skateboard bounces off the ground when a skateboarder does an ollie.
Very convincing! I don't know if I'm hallucinating, but I can also "see" the extra force from the rod, because the rod vibrates when a loop of chain lifts up.
if you know what causality is occurring your brain can chunk your visual input according to the forces you know are present. put another way, if the extra force is real, then it has visible effects, but if it's not real, the things you see must instead be something else. vision is based on inferring explanations for visual behaviors, so the sensation of seeing the forces is likely based on real and reasonable visual chunking, but it wouldn't have allowed you to skip the detailed science because without additional information your vision system wouldn't have been able to select that particular explanation with significant confidence.
The rod definitely is moving- the real question there, and one that would need some real analysis, is whether it's being pushed down by the chain as Steve Mould suggests, or if it's moving up as the weight of the chain is lowering. Or maybe it's just the initial pull on the chain that gets it going?
The acrylic steps test was pure genius. In my mind that's solid proof your right hands down.
yessss. Its simple, functional and... damn, quite impressive how easy its made.
I just noticed that in a bunched up grouping near the end of the run it starts getting pushed down the whole group of chain is moving down. This completely proves you are correct that there's a force pushing back.
I am curious if you have considered what would happen if you had a chain in which each ball got progressively larger or smaller and how the size of the ball may give additional insight?
You should run an experiment with the pot accelerating upwards and see if that makes the fountain rise faster or higher. Basically, instead of trying to remove the kickback force, you increase it
That stair-step test is the best-designed one yet! Although, I will note that the moderate friction with the flat surface will create a tiny normal force for the minimum-radius chain to push against, and thus, I still think the "spaced out on flat surface" version IS a chain fountain, the fact that the chain reacts so clearly against the stairs demonstrates that this minimum-radius effect must act against a normal force of some type to create the "Mould Effect." Mehdi's "just a minimum radius" explanation focuses on the wrong radius (that of the top of the loop) and neglects that the minimum radius also comes into play at the top of the reservoir. I'm on board now with the lever mechanism...
But why does the lever exist? Well, it seems like the peak turn must go to the minimum radius because of the speed of the chain's fall, and the curve between the reservoir and the peak must try to reach a "lowest energy" shape, which will have a large radius. That large radius forces a second minimum radius zone at the top of the reservoir.
This little adversarial competition is awesome, it reminds me of the feuds you read about between renaissance scientists trying to explain the same phenomenon. It's great!!
I searched up mould effect, and it shows up as it. Congradulations mr Mould
I love the fun filled way you are both approaching this! Adding humor is a great way to make an adversarial process not burdensome.
This whole thing reminds me of nothing more than the actions of a whip - one tries to accelerate the tip of the whip past the sound barrier to make a crack. In doing so, you are using the finite flexibility of the material the whip is made from to impart energy along it in a curve, ending with the (albeit narrower and lighter) end of the whip cracking.
The important thing in the above example is the force and flexibility. On the chain, the force is generated by gravity, on the whip it's generated by your body. On the chain, the downward force - once it overcomes the inertia of the chain in the beaker etc - accelerates to it's maximum possible speed. Then, it tries to pull the chain against it's finite flexibility 'curve'. As that happens, the chain rises, just like the wave 'curve' traveling along the whip.
Just my 2c.
Without "mould effect" the maximum speed of the chain is unbounded in a frictionless environment. A simple energy calculation shows this (potential energy equals kinetic energy).
I’m no physics guy, and I’m certainly no longer an engineer, but I was thinking the exact same thing with the whip comparison
16:04 this is how you could test how much force the chain is using to "kick back" by putting the measuring tool on the other side of the pole, you don't have the mass of the chain affecting the readout, therefore you can show/ measure that there is a kickback force and explain it better.
11:43 - Can I suggest an analog gauge. That is - one rough gauge (total weight of chain) and one guage where you put a (still analog) derivator (opamp circuit) so to get the rate of change in real time.
Woah that's great! Sometimes basic is better hey
@Andrew : You actually could do it with a "digital" guage, the trick is that the digital form needs to be reading an average, just like the analog guage would display- usually you'll have to build your own to get customized configurations like that.
@@absalomdraconis The digital gauge is perfectly usable as long as it's not a slow LCD which makes you unable to tell when the reading was completed. Averaging is a whole other problem. You can't avoid having a measurement delay with averaging so you need to time-shift the reading back 'a bit' even for analog gauges.
As much as I love seeing Shatner on the edge of space. I would LOVE to see Mehdi and/or Steve on the next trip to the ISS to keep this disagreement going until they are both in agreement!
i always loved listening in on thesis defenses when i was at school. you really get to see what a theory is made of and how good of a scientist the person is presenting it. rule number 1 is you can't take it personally! rule number 2 is rule number 1 is broken constantly by everyone
Rule #3 don't take it personal.
Rule #4 let it go.
The chain that rises is gaining energy from somewhere. Is the speed that the chain falls at increasing? In the example where the chain height falls, the actual amplitude of the wave you introduce is also increasing, but because the links are spaced out the chain height falls faster than the amplitude is increasing. You put energy into the system when you introduce the wave which sets up a standing wave with resistance to the remaining pile. The energy of the falling chain supports the wave. If you do not introduce energy the chain would never leave the pile. So you are “kick starting” the system basically.
Also, does it work more or less with rope for example? I believe the energy comes form the falling weight and is not dependent on the relative resistance from where the chain meets the pile. A rope experiment would prove or disprove this theory! Actually it is the same principle as water travelling through a tube like a siphon. Only on the chain the tube is a standing wave.
When you start the wave you must introduce energy to overcome the initial inertia. The chain mass needs to be greater than the mass of the chain that rises to the edge of the container. The mass also needs to overcome any friction of the chain rubbing on the edge of the container whose resistance and energy eventually sets up its own standing wave (in the event that you didn’t introduce one).
At 11:25 you can see a kink in the chain has to overcome the added inertia due to greater mass of the link, which requires more energy. The kink takes its energy from the wave and the wave height temporarily reduces and then establishes itself again. It is quite simple really. What would be great is if the energy in the wave created over unity! Any way to measure that? Also, it is helpful to think in terms of energy (not force, force being a component of energy) and what the energy must overcome to do what it does. You must be a mechanical engineer not to think in terms of energy and waves?
I'm convinced, but also hope this friendly duel of hypotheses never ends. I was smiling through the whole video.
Great science content, Steve and Medhi!
Surely this will end. What we really need is a new hypothesis duel to take its place
"It all makes sense" big eyes part missed a fairy like glittering sound to embellish the voice. But I'm reconvinced again.
It's amazing to me that this kind of science is still there to be discovered! It's not based on high-tech equipment, or on new theories like quantum mechanics that have only been available recently. It kind of feels like it's the sort of thing that would have been settled in the 17th or 18th centuries by a Hooke or a Cavendish, and yet here we are just solving it now. It makes me wonder what other questions are still out there that are within the reach of the DIY scientist!
@@IRNoahBody Thank you for your input
Endless boatloads are available to find. Pick a thing you like, get digging. I assure you theres lots of unanswered seemingly basic things to figure out.
@@IRNoahBody someone is mad they didnt figure out the cool chain ghost science
Especially over something as unassuming as a metal chain and a cup.
When was this kind of metal chain made though? These metal chains are hard to make. I wonder if that would explain it.
That said I agree, I believe that if we got given a book of all physical rules, we'd still have centuries of physics left. Both in terms of finding weird consequences like this and also finding useful abstractions for larger scale effects.
Thanks!
Hi Steve, to measure the reaction force on a horizontal plane (9:30), you could try to use a pressure sensitive film like the "Fujifilm Prescale". If the forces pushing against the plate to lift the chain up are high enough, you should be able to observe the forces on the sheet.
This back and forth between Steve and Medhi is like one of those infinite sums that neither diverges nor converges. I think we need Mathologer to help us out.
This is the kind of scientific dispute which I never thought I'd get to witness live on youtube. Excellent work to both yourself and Mehdi for keeping it all friendly and civil, love to see it
This reminds of how large boats utilize their anchors. As the anchor is lowered and the chain released increases the weight of the total load, a braking system has to be used along with a cooling system to prevent a total failure due to heat from friction...
Well, I think the simplest explanation would be this:
If you try different types of chain that have different flexion angles, it will cause the fountain to be lower or higher depends on the bending ability of the chain.
If you just take an ordinary chain without stiffening ribs, it will just drop down like you expect.
I found a TH-cam video of a large ship's mooring chain being released that had this same effect, but horizontal.
@@FelonyVideos 🥲🥲🥲
I think the amount of flex in the chain is a factor in the shape of the 'wave', but not what causes the wave to rise in the first place. The wave will still happen no matter how flexible it is. I think it is friction that causes the wave to propagate, as the chain changes direction it slows down because of friction, but the mass of chain behind it is still moving faster, pushing the apex higher. As the chain falls from the apex, it straightens, reducing friction and it's speed increases again. Which is why the wave doesn't keep getting taller and taller, but settles at a certain height.
@@FelonyVideos no.
‘As you expect.’ Which is?
This is the modern version of Newton, et. al. sending letters to each other, especially when the two correspondents disagree with what is happening in an experiment or calculation.
I keep having to ask myself why I find a bunch of metal beads falling out of a pot to be sufficient entertainment
Its the soothing voice and big blue eyes, it has to be or why the hell we watching a bead chain with such interest! lol
"I’ve yet to see any problem, however complicated, which when you looked at it the right way didn’t become still more complicated.” - Poul Anderson
it's the equivalent of being mesmerised by the most chaotic movements in a lava lamp.
Observe what happens at 20:48 to 20:49, in that transition the remaining chain hanging from the bar moves down as if it is trying to start flowing in the opposite direction and then is pulled up by the momentum of the chain travelling upwards. If we compare the fountain to a mass spinning in a horizontal plain tied with a string pulling up on an equal mass vertically we see that as the spinning mass accelerates it pulls the vertical mass up but as it enters a larger orbit the vertical mass stays stationary as it slows down the vertical mass drops and as the spinning mass enters a small orbit the vertical mass becomes stationary again. If we pull down on the vertical mass the spinning mass accelerates or rather spins faster as it enters a closer orbit to the center of rotation trying to maintain its energy. In the falling chain fountain once the chain hits maximum velocity in the downward direction it no longer tries to maintain its energy by moving to a larger arch, also as it accelerates in a downward direction it also tries to rotate faster and enter a larger arch (orbit) but as it is not tethered and passing into its arch of rotation at different angles, it flaps around like a fish out of water. If there is any downward force being applied to the jar it is falling out of it is caused by the inconsistent location of its departure in combination with the flapping action. Ever drop a slinky down the stairs?
The more organized the beads are the easier they are to accelerate. Any disorganization leads to a dampening affect. If both of you use the same vessel and organize the beads so the direction they want to travel is only linear(similar to a fishing spinning reel) it will minimize variables. I would recommend spooling them in a vessel that's diameter is the maximum diameter of the chains smallest possible diameter. I feel every bead is accelerated differently since the direction is always changing it will be dampened. Just a suggestion, no need to over complicate it...lol good luck.
I think it's three major forces working together: kickback, Mehdi momentum, and standing wave
I would love to see this end with that as the answer. It is an effect of all three culminating in the fountain.
This is honestly most likely; it's unlikely that just one singular phenomenon can explain what we are seeing here.
Brilliant! Often when looking at problems we have different views which seem opposites at first, maybe that's the case here. On one hand you have the inertia of the chain going over the lip of the container or simply continue it's path, on the other hand we need to have a supporting force in the container so that the chain can stand up. The disagreement is sort of a communication problem, when you say that there is an "extra force" it sounds like something absurd like if the container or pile was doing something more than reacting. That lever explanation seems a bit flawed, but yeah, the bending resistance probably helps to create the raised loop.
Imagine a world where people could disagree with each other without getting upset
Right now, (I’m comfortable saying) you have the most uniquely “educational” channel. The video discussion/demonstration regarding a water computer was a completely new topic for me.
Personally, I think it would be fantastic to learn more on the topic of “water” in all (and each) of its various states….and studies involving its resourceful uses.
Thank you Steve :-)
You guys just need to collab TOGETHER for a week. And in the end, the winner has to buy the loser dinner; TOGETHER.
This way it will be a beautiful end no matter what.
P.S. Make sure you include a photo of the dinner bill.
...i mean there is a plague...
Destin @ smarter everyday could be a mediator for a collaboration video.
Here's an experimental setup that may allow for a scale reading: set up a large plate on top of the force sensor. Place the vessel containing the chain on the plate such that the chain exiting the vessel also lands on the plate. Aside from variations caused by vibrations and during the initial non-steady state acceleration, you should be able to average over the entire run to get a pretty good value for the weight - and therefore extra force. Compare this averaged weight to the initial weight of the vessel and chain (less the amount in the air during the motion). Not sure if this requires unattainable precision/accuracy, but it does get around the constantly changing scale reading.
😂 I love this exploration battle, you guys have my attention/ me hooked. Waiting for the parry 🎉
"Why didn't you mention the simulations, Medi?" ... I loved that camera effect, anchoring to your face, way cool!
4:57
You can see though that Mehdi is using a slightly different camera effect, as he moves his head right and left and the camera is not stuck to his head.
One day this entire saga will be recorded in physics books and idk that sounds awesome.
It's like the letters between Kepler and Galileo
@@personzorz Or between Marx, Engels, Bakunin, Lenin and other great minds
A nice idea, but, uh, no, it won't. This is just educational entertainment by youtube creators, not groundbreaking discovery.
The hypnotising blue eyes had me laughing.
I come for the learnin's, I stay for the laughin's
Following the science debate and in the end get better understanding about the problem without anyone getting salty. This was actually great :-D
I’ve loved these series of videos so far, great discussion and interesting phenomenon
How many hours of my life have gone into watching chains fall. Way less than either of these guys at least. I'm loving it.
11:53 "But what I can do is use the force..." - Steve Mould, confirmed Jedi
With the rod setup, has anyone put it on a bearing?
The downward force on the rim of the rod isn't just offset by the cantilever it's also offset by torque.
GREAT suggestion! I think, just after the 5 seconds since I read your comment, that perhaps that would increase the speed &/or height of the "peak" of the up-swinging-then-falling chain ⛓, as the forward-most chain length's upward force would encounter less friction, thereby allowing the upper "fountain" section to be unraveling the chain quicker, not slower [or without the upward fountain manifesting] as in Steve's last simulation clip (where he removes the pole) because the pole is still there to 'push' against. The ball bearings on the pole would just allow it to run quicker, and as I predict, increase the height of the fountain.