World Record Chain Fountain? The Mould Effect Explained

You can also discuss this video over on reddit: stvmld.com/_sv6ydpm but there's a lot of good discussion happening here too! Really happy to finally see Mehdi's excellent video. I want to talk about one of the main points from it that people are discussing in the comments. The horizontal experiment with the spaced out rows of chain (time code: https://youtu.be/hx2LEqTQT4E?t=617) I don't believe it actually demonstrates the chain fountain. The arc never gets "higher" than where it started (I put "higher" in speech marks because the experiment is horizontal, but you know what I mean - "higher" means "to the right" in the case of your experiment). Yes, the loop gets longer when measured from the top of the pile (because the top of the pile moves to the left, but that's just how chains behave, once you're in steady state the chain will just flow through whatever shape it has. The fact that the peak of the loop actually moves "down" (to the left) in Mehdi's experiment is probably due to friction and due to the fact that it didn't start in steady state. The same is true for the experiment he does off the whiteboard (https://youtu.be/hx2LEqTQT4E?t=956). He lifts it up before pulling it down. It's already up to speed by the time he lets go and so almost steady state - the chain then just flows through the loop he gave it. It doesn't rise any higher than that. I would be convinced that I was wrong if someone could show, with the spaced out beads, the fountain rising after they let go.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Your tenacity is overwhelming and profound Steve Mould.

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

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

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

Hi Steve, First of all, I'm a big fan of your channel, please don't ever stop making those videos. When I was looking on this Mould effect (yep, you earned it!), I was thinking what would be the difference between the height of the fountain going up from the pot to how far it will go going sideway from an horizontal pot. Would it rise up the same way? or will it just go as water flow? I think this test can give another perspective on this problem.