I'm trying to understand the 'Lever Principle' and have made up a few questions to help better understand the concept. Although researching the subject I'm having troubles finding any videos or threads containing the idea of fluid being in a hollow tube acting as a see-saw and I'm curious to the idea. The question is if the see-saw or water weight was at an angle if it would act exactly the same as if the see-saw was completely solid aike to a typical lever. I'm also writing up another relevant question regarding the topic that's gets a little bit more into detail.

The photo below has a see saw that's 10 ft in leangth. Each line through it represents 10 lb of water weight so each side of the fulcrum is exactly 50 lb. I understand that its currently at an 80 degree angle and should be equalibrium but please disregard that as I'm just trying to keep it simple for the question.

see-saw filled with water

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    $\begingroup$ Yes, the same. As long as there is no airspace in the tube, the water is not allowed to move in order to be the same as a solid. $\endgroup$ – PhysicsDave Oct 3 '19 at 1:58

It would only make a difference if the water could run from one end to the other, such as a single straight tube with air and water in it. If the water was contained as it appears to be, where the see saw's center of mass did not change, it would work the same as a solid.


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