All Questions
Tagged with equilibrium fluid-statics
23
questions
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60
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An object is connected to the end of a spring and is immersed in water. What are the forces acting on the object? [closed]
The actual question is
A copper piece of mass 10g is suspended by a vertical spring. The spring elongates 1 cm over it's natural length to keep the piece in equilibrium. A beaker containing water is ...
- 91
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2
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46
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Water level in pipe higher than surrounding body of water
I had a question about water pressures and level. We've recently drilled a near vertical hole underground 130m deep by 400mm in Dia into flooded lower underground workings as part of a de-watering ...
0
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51
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How to calculate equilibrium time for a communicating vessel with height difference?
The scenario is that a communicating vessel or a U tube without lids is filled with water. There is a height difference between the two pipes of this tube. Then there will be hydraulic pressure and ...
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1
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96
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Why is the surface of a static liquid always perpendicular to the direction of net force acting on the liquid as a whole? [duplicate]
In a, let's say rectangular container, the water surface always aligns itself perpendicular to the direction of net force acting on it. Why exactly does it happen?
(For example when this container is ...
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What is the total energy of newtonian polytrope stars of index $n > 5$?
In classical newtonian theory, we could find a general expression for the gravitational potential energy of a polytrope sphere (of pressure $p(\rho) = \kappa \rho^{\gamma}$, where $\gamma = 1 + \frac{...
- 7,592
2
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1
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369
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What is the equation of state (EoS) of a polytrope in general relativity?
I'm trying to numerically integrate the TOV (Tolman-Openheimer-Volkof) equations, using Mathematica. The code works, but I'm having issues with the polytropic equation of state (EoS). The equations ...
- 7,592
2
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1k
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Numerically solving the TOV equations: how to find the max radius and mass?
I'm solving the TOV (Tolman-Oppenheimer-Volkoff) equations using Mathematica 13.2, and I'm having some issues at finding the outer radius $r_{\text{max}}$ and mass $M_{\text{max}}$ of the spherical ...
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-1
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225
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In a mixture of two immiscible liquids, why does the denser liquid always settle down?
The same is not true for solids, e.g. an iron block kept over a wooden block.
- 95
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2
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329
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Pressure in an accelerated container
Let us take a closed container completely filled with some liquid.Let us assume that the container moves with some acceleration in the horizontal direction.
Usually when we have such situations,we ...
0
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1
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240
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2 connected tubes filled with water, placing a stopper in one and raising the other, how can I determine pressure exerted onto the stopper?
If I have two 20ml test tubes connected at the base via a thinner flexible U-shape tube and I pour a set amount of water (40ml) into one test tube whilst both are at level height, the water ...
1
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2
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91
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Which force is holding the plates in equilibrium?
I came across this problem which had the given setup: A drop of water (mass = 70 mg) was introduced between two glass plates, assume wetting to be complete, find the attractive force between the ...
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2
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51
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Fluid statics and pressure
Consider a fluid filled in a cylindrical container, height $h$ and area of cross-section $a$. The pressure at the bottom will be:
$$p_0+\rho gh$$
but not
$$p_0+\rho gh+\frac{mg}{a}$$ where $m$ is the ...
1
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2
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450
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Variation of atmospheric pressure with depth in U-tube
In my physics book "Fundamentals of Physics" by Jearl Walker there is a figure that shows a U-tube with uniform cross-sectional area. The U-tube contains two liquids in static equilibrium: ...
- 105
2
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169
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How to derive the hydrostatic equilibrium equation from the variational principle?
I was reading the book "Advanced Stellar Astrophysics" (William K. Rose, 1998) and I came across a different approach to deriving the hydrostatic equilibrium equation. First he defined the ...
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458
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Pressure at the greatest depths humans have dived to without a suit is many atmospheres but humans not crushed, why?
I understand that the pressure can be 50 atmospheres: https://en.wikipedia.org/wiki/Deep_diving.
Okay, I understand also that the pressure is equal all around but if someone was put between two metal ...
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