Hi,
No external gravity here for simplifiy the study please.
I try to understand how the sum of forces can be at zero on this study. A container with water inside turn at ω rd/s. The container is not full of water, so there is air in the center because water is at external radius. A green disk with NO MASS (it's a theoretical study) turn at ω rd/s too. At a time, the disk is moving down water like image showing. The disk has no centrifugal force because mass is at 0. The disk has a force from water because pressure is not the same everywhere inside container. This force is like :
F = πr²hρω²R, with r: radius of tube, h: height of tube, ρ: density of water, R: distance of tube from center of container.
When the tube is inside water, the center of gravity change. The force from pressure to wall at left increase due to the bigger radius. But the center of gravity is compute with linear law, the force of pressure is compute like ω². If the object is a line, it's ok sum of forces is 0. But if object has a width, the force of pressure on object and walls depend of r² and it's strange this is exactly compensated by nex center of gravity. Do you know if this study has already done ? or have you a link ?
No external gravity here for simplifiy the study please.
I try to understand how the sum of forces can be at zero on this study. A container with water inside turn at ω rd/s. The container is not full of water, so there is air in the center because water is at external radius. A green disk with NO MASS (it's a theoretical study) turn at ω rd/s too. At a time, the disk is moving down water like image showing. The disk has no centrifugal force because mass is at 0. The disk has a force from water because pressure is not the same everywhere inside container. This force is like :
F = πr²hρω²R, with r: radius of tube, h: height of tube, ρ: density of water, R: distance of tube from center of container.
When the tube is inside water, the center of gravity change. The force from pressure to wall at left increase due to the bigger radius. But the center of gravity is compute with linear law, the force of pressure is compute like ω². If the object is a line, it's ok sum of forces is 0. But if object has a width, the force of pressure on object and walls depend of r² and it's strange this is exactly compensated by nex center of gravity. Do you know if this study has already done ? or have you a link ?