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Ok there is a dam of width "b" and a liquid is filled on one side of it to a height h. Now I need to calculate the force on the wall of the barrier on the side where the liquid is filled. I considered a small layer of liquid of dx (vertical) at a distance x from top of liquid surface. Then:

int dF= int delta xg (bdx)
limits 0--->h on RHS
f=frac {b delta gh^2}{2}

Therefore the force on the barrier depends on:

- width of the barrier
- The height (h) to which liquid is filled
- Density of liquid
- and g

Now suppose I want to calculate force due to liquid in a cuboid lying horizontally on floor. It's length is l breadth is b and height h ... now if it lies on floor with breadth as its height...then it means as per previous conclusion that length of the cuboid lying horizontally wouldnt make any difference...So this means I keep on increasing its length without any effect on force due to liquid on the front face?

Answerr: WRONG!

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