Explain me concept (Fluid Mechanics)

AI Thread Summary
Atmospheric pressure exerts force on the surface of fluids, and pressure increases with depth due to the formula ρgh, where ρ is fluid density, g is gravitational acceleration, and h is depth. The discussion clarifies that pressure at the same depth in a fluid is uniform, regardless of the container's shape. In a bent tube, pressure remains constant at points with the same height, confirming that pressure is equal along a horizontal line. Even if liquid levels differ in a U-tube, pressure at the same elevation from the base remains the same. Thus, pressure at equal depths is consistent across various configurations of tubing.
snshusat161
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It has been told to me that atmosphere exert a pressure (known as atmospheric pressure) on the surface (I'll take water surface here). And as we go down into water (any fluid, but for instance I'm taking water) the pressure increases. And this increase in the pressure is independent of the shape of the container and only depend upon the depth below the surface of a water open to the atmosphere.

The pressure at depth 'h' below the surface of water is greater than atmospheric pressure by an amount \rho.g.h

Now the confusion begins from here.

First Question

If I bend the tube in this way:

http://www.naugraexport.com/glass/tube-u.jpg

will the pressure will be same at every points having the same height or same depth? Explain if I'm going wrong.

Second Question

[URL]http://www.vias.org/physics/img/utube.png[/URL]

In case like shown above where the surface of liquid is not in same level can we still say that the pressure at any point having same elevation from the floor is at same pressure.
 
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For pressure at any depth you add pgh(where h is measured from top) to pressure at the surface of liquid. The U-tube here has different levels because the pressures at the surfaces are different. However if you draw a cylinder at the bottom of U-tube it is at rest so pressure at the bottom of the tube is same. That will hopefully make you think that pressure of at same height from the base of tube have same pressure.
 
You mean the pressure at the same horizontal line is same, no problem how I bend the tube.
 
snshusat161 said:
You mean the pressure at the same horizontal line is same, no problem how I bend the tube.

Yes at the every point in that horizontal line the pressure is the same.
 
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