Pressure in a Fluid-Filled Glass with a Side-Hole Tube: Is Pa = Pb = Pc?

AI Thread Summary
In a fluid-filled glass with a side-hole tube, the pressure at point A is influenced by the fluid's height and density, but is not solely defined by hydrostatic pressure. Using Bernoulli's equation, it is established that the pressures at points A, B, and C are equal, leading to the conclusion that Pa = Pb = Pc. The kinetic energy components cancel out due to the conservation of mass in a uniform tube. The discussion clarifies that despite initial doubts, the pressures at these points are indeed equal. Understanding this concept is crucial for grasping fluid dynamics in such systems.
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Homework Statement



It's not a homework exercise, it's more of a conceptual question to help my understanding of the subject. Imagine that you have a glass of height H filled with a fluid with density ro and viscosity eta. There is a hole somewhere on a side of the glass, at a height h relative to the top of the fluid. In this side-hole there is a tube attached, uniform, all cross-sections of this tube of length l have the same area. In the tube, which is the thing I'm concerned about (and where the fluid flows out of the glass), the first cross-section is A, the middle of the tube is B, and the end of the tube is C. Okay, my questions are these:

Is the pressure in point A defined by ro*g*h alone?
What is the pressure in point B?
And in C?

Homework Equations



Bernoulli equation -> Pa + ro*g*h + (1/2)*ro*Va^2 = Pb + ro*g*h + (1/2)*ro*Vb^2
Continuity equation -> Sa*Va = Sb*Vb

The Attempt at a Solution



By using Bernoulli's equation between point A and B, for example, I cancel out the potential energy element in both sides of the equation because the height doesn't change. The kinetic energy component of the fluid is also cancelled, because according to the conservation of mass, and given that the cross-section area doesn't change throughout the tube, Va = Vb. That leaves me with Pa = Pb. Is it true that Pa = Pb = Pc? I don't think so, but I can't prove otherwise.
Thanks.
 
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