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BTW, Andrew, a competent Engineer would know how any black box he uses will work because he couldn't risk it failing to perform as he expects when tested. You have been using a black box all the time but have no idea what is going on inside. You're no Engineer. There goes another group of workers who you have denigrated.
I see no point in stating the obvious
Cohesion evident in the flow from one vessel to another is clearly not relying on adhesion
I was relating to your capped end tube all along.
One could go on to argue that the cord used to raise the rope exerts a constricting pressure
I melted the end of a 130 CM length of the same tubing used in the Brixham experiment
Again I must state that there is little to no point repeating the same experiment with a longer length of tubing as the force exerted by the column of suspended water will easily cause the water to be pulled from the tube.
It may interest you to know that when the U tube is performed lower than 10 metres and the ends of the tubes are removed from the water, the water flows out and will not remain in the tubes
I have just read your last outburst, which I will ignore.I was about to post the following reply when I read it.You will notice that I am trying to be constructive.:QuoteI see no point in stating the obviousIt may appear obvious to you but nothing is 'just obvious' in Science. If you have an incomplete model in your mind of what is going on then you can't explain this.The reason that you don't explain it must be because you can't.You are doing to me exactly what you claim that Science teaching is doing to children. What you are saying. effectively, is "You just have to accept this obvious fact". If it isn't obvious to me then are you going to shout at me as if I were a naughty / thick child or are you going to try to help me with my obvious misconception?Which should I do if I were trying to get an idea across to a child who didn't get what I was saying?Some comments:QuoteCohesion evident in the flow from one vessel to another is clearly not relying on adhesionDo you have a cohesion meter and an adhesion meter to tell you this? What justification for this statement? (we are not dealing with a chain or wire made up of a solid substance)QuoteI was relating to your capped end tube all along.But I was, 'all along', asking you to draw a distinction between the two situations - yours and mine.QuoteOne could go on to argue that the cord used to raise the rope exerts a constricting pressure Precisely. The weight of the rope will pull down on the pulley. The rope is a solid and, despite being able to distort a little (become a bit narrower and longer), the 'constricting pressure' is balanced by the molecular forces which are there - the properties of a solid. If you were to hang a length of chewing gum (a very plastic substance) over the pulley the gum would stretch and get thinner because it would flow. Water flows, too, but more easily, so you would expect the same if you didn't provide the tube outside it which could provide some extra forces.QuoteI melted the end of a 130 CM length of the same tubing used in the Brixham experimentWell, you did try. It worked as expected. During your whirling phase, it is not surprising that water flowed out - the tube could flex and bubbles would have been admitted into the bottom, allowing air in. Also, the opening at the bottom would not have been horizontal so there would have been a pressure differential (Hydrostatic - not atmospheric) across the inverted surface of water - that would start a water flow - you can see this happen with an inverted bottle of water, too where the water flows (gloops) out quicker if the bottle is not exactly vertical. If you had suspended the tube motionless and tapped the sides I would expect the same sort of thing to happen. It was worthwhile trying but you were not in a position to see what was actually going on inside the tube. If you were to try the same thing with your U tube, I think the water would fly out even quicker with such rough handling (see the last comment on this post for the reason).QuoteAgain I must state that there is little to no point repeating the same experiment with a longer length of tubing as the force exerted by the column of suspended water will easily cause the water to be pulled from the tube.That presupposes your original ideas are correct and that the inside of the top of the tube was as smooth as the top of the looped U tube.There are many problems associated with implementing the closed tube experiment and I can see how the continuous loop provides both a much smoother surface and a better chance of eliminating bubbles. That is a practical and not a fundamental difference between the two experiments. Very easy to draw the wrong conclusions about the actual mechanisms at work.QuoteIt may interest you to know that when the U tube is performed lower than 10 metres and the ends of the tubes are removed from the water, the water flows out and will not remain in the tubesThat is precisely what I should have expected to happen. It's an unstable situation. Unless the two arms of the tube are precisely the same length then there will be a hydrostatic pressure differential across them causing water to flow. Once it has started, the difference increases further and the flow will increase. If the tubes are kept in small reservoirs, such as in your original videos, the levels will self-adjust. This, of course, explains why, when you added a more dense liquid to one side, the levels started to change; the hydrostatic pressures are not equal. If you were to raise the side with the salt in, you would find a new position in which the flow would be zero. (Until diffusion of the salt solution into the freshwater side started to change things).To sum up, I can see nothing in your last post which proves or justifies further you explanations. Half way through you, yet again, beg the whole question by making the assumption all over again.All you have described fits in perfectly with conventional theory. I think I have identified the crux of our differences enough times. Are you really not capable of answering my one small point about the way the molecules must be working 'at the top' IN BOTH CASES?By the way, bubbles being admited into the bottom of the whiling tube will not alter the adhesion at the top of the tube with a mere two rotations will it? How do those bubbles travel from the opend end to the top of the capped tube while it is generating centrifugal force towards the ends of the pipe? What really happens in the tube is that the weight of the water exerts too much force on the molecules stuck to the top of your domed capped tube ending.
The tension BTW should be the same throughout the water column,
Glad to see everyone is being so cordial, courteous and gracious  
You say water would move away from the inside of the tube. As water is already compressed by gravity, where is it going to move to? It can't move down the tube because it is linked to other molecules balancing the downward pull equally on the opposite side of the U tube. It canít flow out because this would require cavitations to form, again to break the cohesive bond.
The heat source alters the density of the water causing it to rise.
Your post asking about the void related to the single capped tube. I said that water flowed out of the tube when the experiment was performed, so could not have returned to fill up the void.
water molecules will always move to where molecules have moved from,
I did mention that as one molecule moves away from the wall of the tube another will replace it
OK on the term 'density flow'. In a hot water (convection) system, the energy comes in the form of thermal energy. To keep it going you need to keep the energy flow by maintaining a temperature difference.QuoteThe heat source alters the density of the water causing it to rise.That's schoolboy howler number one. Water will not rise unless it is pushed. There are no strings pulling it up. What pushes it? It is the more dense cold water which displaces it.Andrew, if you are not thorough with well known matters like that then how can you hope to make any worthwhile advances in Science?QuoteYour post asking about the void related to the single capped tube. I said that water flowed out of the tube when the experiment was performed, so could not have returned to fill up the void.So what was in the space over the water? If there was a permanent 'void' at the top then it must have been AIR! That means either a leak into the top or bubbles floating up from the bottom. I wish you could explain exactly what happened. It certainly casts doubt on the experiment.Quotewater molecules will always move to where molecules have moved from,Here's another cause and effect problem. The more dense solution displaces the less dense. Why? Because the more dense is pulled down harder than the less dense and pushes it out of the way. When you add the solution, you increase the overall pressure at the bottom of the container.How does that apply to molecules as they move from the surface when water evaporates? You imply that you would get 'strings of water' leaping up into the air.The moecule I mentioned was a water molecule, so presumably it would have come from the water inside the tube.QuoteI did mention that as one molecule moves away from the wall of the tube another will replace itAnd where does this molecule come from? Does ther have to be a flow? Do you inject them into the top? Get your model sorted out; it really is dodgy. Or are you only considering the situation when you have enough gum flow to allow the molecules to come from the other side? You are implying that there is a minimum speed at which this would work. Any slower and the gum will 'neck'. My diagram applies to the gum just the same as the water. Are you arguing with the basics of force vectors?
Remember. The U tube experiment was relating to the shape of vessels in nature. Trees do not have tall tubes that flow up to the top and end, they have circular vessels that entertain a circulation, something worth remembering.
Your experiment idea is a test of adhesion, and yes I do understand why you feel this may be strong enough to support the water.
You keep trying to throw a protective shield around students steering them from what you see as heretical science. But then fail to address the flaws in the accepted science.
The fact that you have a problem with what goes on at the molecular level inside a U tube compared to the inside of a capped end tube is fascinating but hardly going to destroy my own observations whichever way it goes is it?
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