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Physics/gravity &buoyancy


QUESTION: Dear sir . I send image .we are already discuss about i made changes in image .this is my last try,ok or not ok.


ANSWER: No, and for the same reasons.  The 60kg of water on the left doesn't matter, because it reduces your buoyant force on the right.  The problem comes with the structure you call "damper," which appears to be some form of airlock.  This will not work, though you are welcome to draw it in further detail (buckets entering and leaving it.  At some point it cannot be filled with vacuum, so it must be filled with water or air.  

If it is filled with air, then the air must be displaced when the bucket goes in (easy)...but in that case you still have to overcome pressure resistance to draw the bucket into the larger water-containing structure (same force problem as before).

If it is filled with water, then you must displace that water to get the bucket inside the damper structure, leading to the identical problem.

You are welcome to re-think the "damper" and try again, but this still does not work.

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

QUESTION: Dear sir.
         1.Any possibility to left the weight at above the water surface by buoyancy force of water. ? .

         2.A weight fall down by gravity.  It workdone will above the weight or equal or less. ?.

Well, first these questions aren't formed in a way that I can make much sense out of them.  Perhaps you can rephrase them more carefully.  Buoyancy of water has no bearing on the work done on the left hand side of this diagram at all.  It still won't work.  People have actually attempted (and failed) to build such devices, you know.


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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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