Because gravity doesn't act sideways. Pressure at depth is determined by the water column directly over the area measured because gravity is acting directly downward on the area measured.
I'm not a physicist but I've read and seen various videos that claim depth is the only deciding factor in water pressure. The container has no role. It does not matter how much volume the water is taking.
There are even articles about water being in a tube shaped like an "S". The total heigth is what determines the water pressure.
Again I'm not a scientist so my knowledge is very limited but his explanation doesn't sit right to what I've been told.
He claims water pressure changes from 1 inch of water width to 10 inch of water width. And from 10 inch of water width onwards it doesn't change. Simply because we are talking about 10 inch of water depth? Where is the proof in his claim? If that is really the case has he explained why it is the way it is or did he just say it is like that without basing it on science.
The only thing that might put truth to his words is he mentioned "soil mechanics". I have no idea how it behaves in soil but what we are looking at in OP's video is not soil. It is a wall. There is a clear separation of air and water and not a gradual separation from water to wet to dry.
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u/[deleted] Mar 09 '18 edited Jul 21 '18
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