1. the height rising and falling is directly proptional to the acceleration of the falling part of the chain???
   and with a constant velocity, height remains same
   minor differences may be due to imperfections

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2. Mechanics is a pretty deceiving subject. I scored great in almost everything, took up a course in mech, thought it might be a cakewalk.
   I walk in the exam hall, come out half an hour earlier and got a C.
   Seems like what I thought was a half a line answer turned out to be pretty nasty results with a bunch of ghostly constants floating around in it…

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3. I agree with you. Lever has nothing to do with it. In the beaker test in order for the arc to rise the links moving upward would have to travel faster than the links moving downward. This stands to reason correct? What would explain this? F=MA. The mass of links moving down is increasing. The mass of links moving upward is not increasing. Force along a chain is constant. The smaller mass with the same force accelerates faster. A= F/M As you noted an equilibrium is reached and the arc does not rise beyond that point as the speed becomes constant. A goes to zero. I propose a test where the entire length of chain is free hanging and running over a pulley to prove it is not pushing against the bottom of the beaker. Put a weight on the falling end to make it accelerate. I'd try it myself but do not have 100' of ball chain laying around.

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4. Every piece of the lever effect and inertia and friction adds energy to the chain that resonates and must escape it's held by some degree in the pot and chain at the same time and your seeing the energy meet in the arch and accumulates. Like anytime two waves collide they combine momentarily while passing through each other… Well what your seeing is a resonance of that effect in the wave. you both already know this as explained in your other vids about energy waves!

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5. ElectroBOOM,

   Here is my comment on Steve Mould's recent video. What do you think?

   Steve Mould,
   There is no force "from the pot". The answer is rotational force. This is all explained by rotational force, and the design of the chain and the fact that it can bend freely, but only to a hard limit and can never fold completely over on itself. When the chain is pulled with enough force up, then whipped down, the chain bends. Then a rotational force is created and energy is transfered around the bend like it is riding on a virtual gear. This is even apparent when there is a pile of chain on the table, and the chain simply falls off the edge. The bend in the chain as it goes over the edge creates a rotational force and the edge of the table acts as a virtual gear for the chain to go around until the chain speed increases to the point that enough force is transfered around the virtual gear to cause it to rise. In this case the rise is small because it is effected by friction and bouncing as it contacts the edge of the table, and the direction the chain is pulled from the pile which is not always straight up and often horizontal. No force is applied downward into the pile of chain nor is it needed. The force pulling the chain is maintained by gravity pulling down on the falling part, then transfered around the virtual gear causing a rotational force, which then pulls the chain from the pile. The chain "fountain" rises when the speed of the chain rising to the virtual gear is sufficient to overcome the gravitational pull on the rotating portion of the chain at the virtual gear. This rotating portion of the chain with it's rotational force, as if it were around a virtual gear, is the key to what we see in chain fountains. It is exactly what you would or should expect. Trying to explain this is impossible without understanding the powerful rotational force at the virtual gear which is fed energy by the falling chain being pulled by gravity. Also note that the energy pulling the chain is not a constant and even force as a chain pulled tight In a straight line would experience. The energy is traveling up the chain in a wave and some parts of the chain are being streched and jerked while other parts are not and this force is like a continual wave repeating the starting force using gravity to feed it. No real mystery at all…

   P.S. In your test with the chain spaced apart, the fountain did not receed relative to the point the chain was being pulled from. It only appeared to receed because the point the chain was pulled from was continually receeding as apposed to the pile of chain which maintains a relatively fixed position. This is easy to see in your side by side of the two test. If you were to do the standard chain fountain and lower the "pot" as the chain came out you would see the same effect…

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6. I am going to use this video to teach my science students how to recognize flawed logic and irrational reasoning skills. Thank you for continuing to be wrong and bad at science so I can teach the next generation how to not be like you.

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7. ElectroBOOM is right.

   It's simple physics, potential energy, inertia, centripetal force, etc. There's nothing fancy going on at all. Steve's hypothesis isn't right. ElecroBOOM is spot on.

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8. The Cambridge explanation is rubbish.
   
   There is never a bonus-kick at the container/jar/beaker.
   
   There is indeed a bonus-kick when a falling chain-link hits (collides with) the floor of the laboratory, & this adds to the downward pull of a chain, & increases the size of the fountain etc (by say 1%).
   
   But that extra (bonus) force is initiated by the falling/colliding link itself.
   
   Meanwhile, back in the jar, a rising/yanked link will indeed get a kick from the floor of the jar (or from the links supporting that link), but, that kick is not initiated by the rising link, it is initiated by the preceding link.
   
   The preceding link has a limited amount of impulse to give.
   
   The kick from the jar results in a similar (but opposite) kick being given to the preceding link.
   
   But the kick from the jar is not a bonus-kick.
   
   The initiating impulse from the preceding link is not added-to by the kick from the jar.
   
   The impulse of the kick experienced by the rising/yanked link has been borrowed from the preceding link.
   
   In reality, borrowed from the full/whole chain.
   
   Hence, at the jar, links or beads, it makes no difference.

   In reality, there is no rising/yanked link. Duznt happen.
   
   What i mean is, we mostly have a rising/yanked arc, made of many links.
   
   In slow-mo u can see that there is mostly a long arc of moving links (talking bout metal beads here).
   
   And the movings usually involve being dragged gradually horizontally for a time, & gradually upish.
   
   There is no sudden kick — it is a gradual kkkiiiiiiiiiiiiiiiiiicccccccccckkkkkkkkkkkkkkk.

   Look in slow-mo at a bead chain fountain.
   
   There are say 4 adjacent beads acting as pseudo-links being yanked/jerked up.
   
   (a) But, these pseudo-links are not rigid, they have a lot of give.
   
   (b) And, these & the trailing say 5 or even 10 beads are moving horizontally & have daylite under them.
   
   (c) The pseudo-links never have a solid floor to kick (down) against.
   
   (d) And, even if the last bead in the pseudo-link does enjoy an upwards (very very weak) kick, this kick is off a slippery & lose bead or two, & the kick moves thems beads sideways (or forwards)(or backwards)(they are after all lose in every way).
   
   So, beads do not provide anything like a solid surface to kick offa.
   
   Sheeeesh! Stone the crows! Milo give me strength! Are we blind!

   The fountain (ie the arch)(the half circle) is simply due to the inertia of a chain.
   
   If a stationary chain lays over the top of a wall, it forms a sharp V-bend.
   
   If the chain is pulled down on one end, then it will rattle up & over the wall, with some speed.
   
   If the speed is sufficient, the sharp V-bend will become a U-bend, due to centrifugal/centripetal forces opening up the V.
   
   If speed increases, the U-bend opens further.
   
   If speed increases a lot, the rising chain leaps up clear of the wall, & stays clear, the zenith/crest depending on gravity, & the U-bend opens some more.
   
   And we have our fountain.
   
   The height of the crest/fountain depends on speed (& is probly higher if chain heavier).
   
   The radius of the U-bend/fountain depends on speed (& is probly larger if chain heavier).

   Steve Mould & others say that the radius of curvature cancels out in the equations, & doesn't play any roll in these dynamics.
   
   Steve is wrong.
   
   If he were correct, then that would mean that the radius can vary greatly, for any given setup.
   
   It might mean that if u initiated the fountain with a given radius then it would affect the final (maximum)(steady state) radius.
   
   But i reckon that the radius (for a given setup) tends to one number.
   
   And i reckon that the radius (for a given setup) varies with speed (ie varies with drop).
   
   Just koz the radius cancels out in some dynamical equations duznt mean that radius duznt play any roll in the dynamics.

   Steve Mould shows how a horizontal tight pattern of rows of chain (beads) gradually moves away to the west (due to the kick-effect) when the end of the chain is pulled east.
   
   Yes, there is some kick effect, due to the pseudo-links.
   
   But, the greater part of the effect is due to a chain's inclination to retain a pattern.
   
   Here, we see that at each end of each row the chain forms a loop, looping around & back throo say 220 deg, such that the rows are hard up to each other.
   
   As the end of the chain is drawn east, the end loops move across & back & across & back etc.
   
   Now, Steve knows that a chain has a memory, ie it tends to retain a pattern.
   
   In this case, that pattern is a 220 deg loop.
   
   And, as the loop or loops traverse across & back etc, the loops slowly push the rows west.
   
   That westwards slow pattern-push is a different animal to the quick jerk of a pseudo-link kick.
   
   The slow pattern-push duznt suffer from the hi losses suffered by a pseudo-link kick.
   
   Pseudo-links are not rigid, they have give. Give aint a problem for a slow westward pattern-push.
   
   I said that yes there is some kick-effect.
   
   But, i have already said that these kicks are not bonus-kicks.
   
   They borrow from the overall power of the chain system.
   
   They don’t add to the fountain.

   It is virtually impossible to load/store a chain in a jar without having loops.
   
   And loops result in jumps.
   
   If u have a close look (in slow-mo) u can see that chains have a lot of horizontal movement before exiting vertically, & the chain sometimes suffers little jumps in the jar, as each leg of each loop jumps (horizontally) over its mate.
   
   Jumps magnify the fountain, kicks dont. OOPS. No, i am wrong. These little jumps are not bonus-jumps, just like the kicks are not bonus-kicks. Any vertical impulse gained by a jump must have been borrowed from preceding links.

   Also, the horizontal movements seen in the container/jar/beaker are a waste of impulse.

   But, in any case, we don’t need bonus-jumps nor bonus-kicks to achieve a growing fountain, & to achieve a very high fountain.
   
   All we need is lots of speed. The chain will crest at any height, depending on speed. There is no limit.
   
   The idea that something special (like a bonus-kick) is needed (if the chain is to rise above the edge of the jar) is silly.

   One thing that everyone has missed, in every youtube re the chain fountain (that i have seen), is that vertical jump effects & vertical kick effects (etc) are cumulative, and lasting (tautology alert).
   
   Or at least partially cumulative & lasting. Air friction, & link friction see to that.
   
   Anyhow, cumulative/lasting effects are the reason for some of the slightly weird gyrations/waves.
   
   For example, it (lasting accumulation) is why we eventually get a persevering, vertical component of arc (a mini fountain) when the test seems to be strictly in the horizontal.
   
   In fact, the lasting/cumulative effect is the main reason for the fountain.
   
   There needs to be an initial vertical rise out of the jar.
   
   A horizontal initial exit wont do the trick.

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9. Steve's tests & footages are ok, but his explanations are wrong.
   
   Your explanations etc are good.
   
   Steve makes a mistake in every instance.

   (1) In one case Steve has a chain feeding horizontally off a table, & he expects the chain to gradually rise to the vertical & form an up & down fountain.
   No, a horizontal chain feed duznt form an up & down fountain.

   (2) In other cases Steve shows horizontal chains being pulled horizontally, & the chains rise & arc upwards.
   But this is koz the chain is in small loops, & as each loop closes & disappears, one leg of the loop has to jump over the other,
   hence there are lots of little jumps, & a large upwards & then downwards curve.
   These jumps have got nothing to do with the supposed upwards kicks supposedly experienced by a chain feeding up out of a container.
   If the experimenter had formed the loops with the first leg under the second leg (instead of over), the jumps would have been smaller or non-existent.

   (3) Steve places a chain on a horizontal surface, in one instance using an open non-touching pattern, & in another instance using a tight closely wound touching pattern.
   And he shows that a high fountain forms for the touching pattern, & a not very hi fountain forms for the non-touching pattern.
   And he says that this confirms that chain links kick.
   But if u have a closer look u can see that the fountains have the same height (measured horizontally here), if u measure from the top of the pattern.
   The peak of the fountain for the non-touching pattern moves quickly down koz the loose patterns disappear quickly down (& the peak has to follow)
   (koz if it didn’t follow then the drag of the upwards sliding portion of chain would grow too much)(as the upwards sliding portion lengthened).

   (4) Steve criticises the ElectroBOOM footage of the fountain made of sinkers along fishing line.
   He says that the fountain is firstly made by a hand movement (instead of forming by itself),
   & he says that after that the fountain quickly gets smaller/lower (whereas for a proper chain the fountain grows higher).
   He ignores the fact that if he made a very large fountain using proper chain, using his hand, then that fountain too would quickly get smaller, for a while.

   (5) Steve gets a very impressive high fountain using his drill-winder.
   But using slow motion (0.25) i can see that the chain is getting lots of little jumps in the container, as each leg of each loop jumps (horizontally) over its mate.
   If u go back & look at his footage in (2) of a chain being pulled horizontally on a floor, u can see that these kinds of jumps can be severe.
   His fountain was impressive koz of jumps, not kicks.

   As u have pointed out, the Cambridge explanations are rubbish.
   
   There is never a bonus-kick at/in the container.
   
   There is indeed a bonus-kick when a link hits (collides with) the floor, & this adds to the downward pull of a chain, & increases the size of the fountain etc.
   
   But that extra (bonus) force is initiated by the (colliding) link.
   
   In the container a link can/will indeed get a kick from the container (or from the links beneath), but, that kick is not initiated by the rising link, it is initiated by the preceding link.
   
   The preceding link has a limited amount of impulse to give.
   
   The kick from the container results in a similar (but opposite) kick being given to the preceding link.
   
   But the kick from the container is not a bonus-kick.
   
   The initiating impulse from the preceding link is not added-to by the kick from the container, it is reduced by the kick from the container.
   
   Hence, at the container, links or beads, it makes no difference.

   The fountain is simply due to the inertia of a chain.
   
   If a chain is forced to go up, then forced to veer to go horizontally, then forced to veer to go down, the chain will form a curve or a bend or somesuch.
   
   The change in direction will result in strong, uneven centrifugal/centripital forces, which eventually (can) result
   in the initially sharp curve expanding & rising to reduce the centrifugal forces & to even them out.
   
   Hence we get a larger softer more even curve, ie a fountain effect.

   It is virtually impossible to load/store a chain in a container without having loops.
   And loops result in jumps (koz if u have a close look u can see that chains have a lot of horizontal movement before exiting vertically).
   Jumps magnify the fountain, kicks dont.

   But, in any case, we don’t need jumps nor kicks to achieve a very high fountain. All we need is lots of speed. The chain will crest at any height, depending on speed. The idea that something special (like a kick) is needed (if the chain is to rise above the edge of the jar) is silly.

   Collect your C$10.00.

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10. I have another theory and think all of you are wrong. The effect has two important things happening.

    One is the smooth curve produced due to the even density across the length of the chain. Obviously the ball chain is not even at all as it goes from ball to link to ball again however the balls are spaced very close together giving us a pretty even density across the length of the chain. Just think about a whip that will create the same curve but much more smooth than any chain will ever do.

    Second and the most important I see the chain storing energy as it accelerates right before picking up the next ball jerking it upwards. So basically the energy stored as kinetic energy is used to suddenly jerk the next ball upwards as the link stops inside the ball and suddenly provides the jerk.

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11. You were starting to convince me, then you completely made me not care about the argument at all and distracted me with the real question at hand.

    You have a central vacuum system in your house? How? Why? How does it work? What powers it?

    THESE ARE IMPORTANT QUESTIONS

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12. I was just rewatching your video on the chain fountain and it occurred to me that I didn't see a good explanation of how the effect builds up. So I had a small thought experiment.
    Suppose that you have a very long chain lying in a straight line on a (also very large) table. Further suppose that there is zero friction, and that the chain can bend extremely well. Now we take the tiniest part of the chain and let it hang down from the side of the table. Gravity will start pulling the chain down, because there is no friction to keep the chain on its place. In the beginning the speed will be low and thus the chain will in the beginning fall down without a serious radius.
    But as speed builds up, you would also expect to see a parabolic curve to build up (horizontal speed of the chain, and the vertical gravitational force). However, in the mean time the part of the chain that is already falling has gotten some significant mass, and this mass will counteract the occurrence of this parabolic curve: a parabolic curve would mean that the tip of the chain would not only fall down vertically, but it would also need to move horizontally. So it's just inertia that keeps the falling chain more or less on its place. And now it becomes interesting: will the chain move only horizontally and then down and then bend back to get in line with the already falling part of the chain, or will it also go into other directions to get rid of its horizontal speed and then change it into a vertical speed? It's only logical that this occurs and the result is a standing wave once you reached equilibrium. So the wave-like oscillations in the rising chain must occur, it would be strange if they didn't.
    I guess that your experiment with the chain that is lying on the floor is a 2D approximation of this phenomenon, and to me the form of the wave shows a striking resemblance to ringing of a square wave… Something with signals and Fourier maybe?

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13. There’s a flaw in the black painted bead experiment. If the black bead is distance x from the end of the string, then all the experiments would have the same artificial height at that time. This is assuming none of the string has hit the ground yet. The drop height is the difference in elevation of the bead’s starting position and the current lowest bead. It’s not the starting elevation of the bead system as the experiment depicted

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