- #36
russ_watters
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No. As you said, "the downward water pressure on the support has removed". That's it. Downward pressure has been removed does not equal upward force, it equals zero force.Mapes said:To those saying that the buoyant force completely disappears if liquid is excluded from the bottom of the cylinder, please consider again my diagram in post #20, where no liquid contacts the cylinder bottom, but I predict a measurable upward displacement and associated force. Is there an error in this reasoning?
[separate post]I made a diagram with similar reasoning to Studiot. Consider an object with a strain gauge attached, rigidly attached to the container bottom (welded or epoxied, say, so that no liquid can get underneath). I've marked the downward water pressure that acts on the top face of the object; of course, water pressure is exerted on the other faces also.
Now attach an empty cylinder to the object (rigidly by welding or epoxy, so that no water can get underneath). The downward water pressure on the support has now been removed. The support and strain gauge will therefore elongate due to this change in stress.
Does this not represent and measure the buoyant force of the empty cylinder?
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