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QUESTION: What will stop the objects from floating?
I have a question,

I have a inverted U shape hose. One end is 5 feet high and in a pool of water. The other end is connected to a large funnel and the funnel is in a pool of water 4 feet from the bottom pool. 5 feet - one foot. In that large funnel is a vacuum that hold water at the other end to 5 feet. On moving water. On the bottom end I have a funnel that guide objects that are half the density of water. The objects stack 1 foot high in the water so I have another foot in the water(half density). But the object are a inch long so when it get in the water it want to float up, once it reaches the tipping point it will float in side the hose and to the 5 foot top. There it hit the vacuum and because of the bouyancy the objects (more under the water) under push the ones on top to the other end(funnel and vacuum). There the same system applys, into to a funnel and forces the objects under water till the tipping point where they go up and fall out 3 feet to the funnel at the bottom. Will this work? You can see half of it at

ANSWER: Of course it won't work.  The objects have no mechanism to submerge below the surface, for one.  Even if you put in a big stack of them in your funnel to drive one under (not shown in the video), it won't work because secondly, they have absolutely no way through that door from vacuum into atmosphere, there's no way they'd push out against full atmospheric pressure.  Third, no vacuum would maintain with an opening and shutting door.  I'm an expert on vacuum systems, the energy needed to drive a pump at that end would be prohibitive.  Fourth, it violates basic laws of physics to set up a loop with net forces going all the way around that loop without an internal input of work.

It won't work, period.  

---------- FOLLOW-UP ----------

QUESTION: That video was just to give you an idea as to the concept, objects moving from one atmosphere into another.(See drawing ) So this siphon type vacuum will not hold water? In that vacuum objects will not have enough weight to push the objects on the bottom over( under the tipping point )the tipping point? There is not enough weight or buoyancy to make this concept work? Not looking for engineering just theory.

Joe Arroyo

Well, the upper diagram is too small to read and makes little sense...but the lower diagram is absolutely right out.  The siphoning is all wrong, it doesn't account for surface height differences between the two areas, both connected by vacuum.  Not even close to working in theory, forget the engineering part.


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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