All Questions
Tagged with classical-mechanics pressure
102
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Work performed by hydrostatic pressure
One should be able to show mathematically that the hydrostatic work done by an environment on an object undergoing a volume change $\Delta v$ should be $p \Delta v$, where $p$ is the (constant) ...
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Finding Exterior Confining Pressure from Interior Pressure Point for a Solid Disk
Essentially, I've been wrapping the pictured object tightly with string to exert a confinement pressure on its exterior. It's been difficult however to make a good estimate of how much pressure is ...
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Stress tensor from forces
Consider a body that is acted on by a variable external force density $\vec{f}(\vec{r})$.
I want to know what the pressure and shear stress would be within the body as a result of these external ...
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Fluid Pressure on a curved surface
In this question (b) , I was not able to understand why the upward thrust on the flat surface of the hemisphere will be piR^3, because the "2/3 pi R^3" amount of water has been occupied by ...
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Problem while calculing the bending torque of internal air pressure in a soft actuator
this is a question I cant resolve while looking a paper I needed for my undergraduate thesis.
In this image (from Modeling of Soft Fiber-Reinforced Bending Actuators, Panagiotis Polygerinos et al.), ...
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Help me understand extreme pressure
So we have the tragedy of the submersible being lost near the Titanic site.
I am trying to understand the pressure the vessel was under. I have heard the "$1$ atmosphere for every $10$ meters&...
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Isotropy of fluids vs. hydrostatic pressure (conflicting concepts to me)
The formula for absolute hydrostatic pressure on Earth is
$$
p = ρgh + p_{atm},
$$
where $ρ$ is the density of the liquid, $g$ is the gravitational acceleration, $h$ is the depth of the liquid, and $...
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Why the $\Delta$ in the definition of pressure? (fluid mechanics)
I'm an engineering student (first year) studying Physics 1 (now an introduction to fluid mechanics).
Q1
In my physics textbook, the "medium pressure" is defined as:
$$p_m = \frac{\Delta F_{\...
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Pressure force exerted by one half of the sphere into his other half
lets say we have some sphere under some pressure and I want to find what is the force pressing one-half of the sphere toward the
opposite half?,lets take one piece of area then the pressure force ...
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How is pressure affected by horizontal force in fluid?
In the situation shown above, Point A is just near the wall at negligible distance. But how is pressure at A is due to weight of water and atmospheric pressure only,why does it not have any pressure ...
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Pressure exerted by a photon
According to several sources, momentum of a photon is $\dfrac{h}{\lambda}$.
While doing some reading on radiation pressure. I came across this wikipedia page where it was stated that "pressure ...
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Why are pressure differences so deadly?
The question comes from this video https://www.youtube.com/watch?v=2w-U5wJafhg which details an incident that occurred at the Byford Dolphin Rig https://en.wikipedia.org/wiki/Byford_Dolphin
A group of ...
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Uniform stress toroidal pressure vessel shape
For simply connected surfaces of revolution and uniform stress the shape is a hollow sphere.
What should the shape or thickness variation be for a hollow torus ( like an automobile inflated inner tube)...
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How does pressure act evenly in all directions in interactions between solids?
Pressure is a scalar quantity, and I think I understand this in the context of pressures exerted by gases and liquids. However, I struggle to understand this in the context of solids. If I use a ...
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Why does the Pascal's barrel experiment need a tall column of water?
This question is based on the content of this video .
The experiment consists of putting a tall, thin column of liquid on top of a barrel filled with water, so that the pressure caused by the large ...
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Support Reactions of Columns placed on Hydraulic bed (same pressure) with Unequal Loading
Suppose columns are supported on a deck with hydraulic cylinders which are coupled together with the same pressure. These columns are loaded with unequal loads F1 and F2 (F1 > F2). Will the ...
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Why does the piston 2 not accelerate faster than piston 1 when piston 1 is pushed?
Let say there are two pistons, $p_1$ and $p_2$ such that $p1$ has lesser area at its base and $p_2$ has larger area at its base. Then, by pascals law(pressure remains same everywhere on surface ...
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Why doesn't a blunt-tip nail crack the wood?
I came across this video, which shows you how to prevent the wood from cracking up at the ends while hammering a nail into it. The proposed solution is to make the nail tip blunt using a plier. This ...
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Pressure inside a soap bubble made in a vacuum
A question I came across:
A soap bubble is made in vacuum by blowing an ideal diatomic gas in it. Assume the heat capacity of the soap film is much greater than that of the gas in the bubble. What ...
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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 ...
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Sand cone in the attic [closed]
My question is based on Halliday books Tom 2, chapter 13 (exercise 42).
There is a cone of sand laying in the attic. Consider stress of the floor under the sand cone.
Why the biggest stress is in ...
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Pressure and velocity in fluid dynamcis
I want to ask whether someone could help me solving a problem in understanding the relationship between pressure and velocity in fluid dynamics, please?
Why do I know that particles are not by ...
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How can we take pressure of ideal gas be equal to pressure of atmosphere if container is open
I can better put my doubt in form of problem:
The temperature of a gas placed in an open container is raised from $27^o$ C to $227^o$ C. The percent of the original amount of the gas expelled from the ...
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Pressure inside when a container is closed
Let us suppose that there is a container with its lid open sitting at the bottom of an ocean. The pressure at the bottom of the container will depend on the water column above it assuming only static ...
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Sunlight-powered device set to change world: will it work? [closed]
Vast areas of desert sand are being shone on upon by the sun. Now that's some ENERGY!
Using this proposed apparatus:
Sunlight over large area is concentrated on steam chamber, where water turns into ...
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At what rate does oxygen un-dissolve after releasing pressure?
I have a soda bottle (consider no leaks) at room temperature and 55 psi. Oxygen is saturated in the water inside. After removing the cap, what law or formula can I use to estimate the time oxygen ...
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Dissolving air in water using a bicycle pump
Forgive me if this is dumb.
I connect the bicycle pump tube through a hole in a water bottle cap (half-filled with water) and place it in the water and then completely seal the setup. Then I press ...
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Importance of fluid mechanics and mechanics in physics and pipes
How does mechanics help prevent the pipes from bursting?
How does it link to the pressure of a pipe?
How does fluid mechanics link to physics when its about the liquid phase of chemical processes?
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Air Pressure Acting Below Object
Consider an object resting on a surface. If I had to find the net force on the object, I would write an equation as follows: weight = normal force.
But what about the air pressure that's acting on the ...
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Is atmospheric pressure balanced on an object as it moves?
Consider a box sliding along a friction-less floor at a constant velocity.
Now typically atmospheric pressure is 14.7 psi on all surfaces of the object. But if it is moving at a constant velocity, ...
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Why isn't there a "parallel" Pressure as there is a parallel or shear Stress?
I had this question while I was reading the differences between pressure and stress.
As I have read:
Pressure is the intensity of external forces acting on a point, and it always act normal to the ...
user260844
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Why does compressible fluid flow choke?
The most common explanation to this phenomenon which I have read is that the pressure disturbance signal cannot propagate upstream, as the medium in which it travels itself flows downstream, so ...
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Formula for pressure using this equation for force
I have for a plane surface the following equation for force.
$$F(x)=b \rho lxg$$
Where the force moving along the $y$ coordinate doesn’t change. I need to calculate the pressure in an area in the ...
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Is force due to pressure equally distributed?
Pressure is defined as: $$P=\frac{F}{A}$$
My question is what if we want to find the total force in area of $\frac{A}{2}$. Would be equal to $\frac{F}{2}$? I think that is not true unless we know that ...
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Statistical Mechanics: Particles on a Sphere
$K$ identical particles of mass $m_0$ are bound to move on a sphere of radius R. The system is at equilibrium at temperature $T_0$.
1 - What's the internal energy ($E$)?
2 - What's the specific heat ...
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Why does the red arrow generate smoke when flying at high speed on a moon rocket?
Why does the red arrow generate smoke when flying at high speed on a moon rocket? I think it is because of the structure, the air in this location has expanded, so the air in this location has ...
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Understanding the relationship between $P=F/A$ in brain ventricles
Humans have a hollow space (see the colored part in the diagram below) inside our brain where cerebrospinal fluid is produced and circulated.
A disease exists called "normal pressure hydrocephalus" ...
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How can I calculate the pressure at every point under a block, which rests on a slope? [closed]
A cubic block with uniform density $\rho$ and side length $a$ rests on a slope, with one of its face facing directly downwards. The slop is inclined at an angle $\theta$ with the horizontal. Assume ...
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Does water pressure have any effect on the size of a permanent magnet's magnetic field?
If a permanent magnet is dropped into a deep body of fresh water such as Lake Superior, as it descends down, the rising water pressure should continually reduce the size of the magnetic field ...
user217618
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Is the air mass density in the International Space Station (ISS) higher than that on the earth at sea level?
I have read that the atmosphere in the ISS is pressurized to a standard sea-level atmosphere and also of the same composition (ratio of nitrogen and oxygen etc.). What I am struggling to find online ...
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Is it momentum/force or pressure that determines the damage of an impact?
So a tiny object and a huge object that have the same mass and velocity strike a surface. Because they have the same mass and velocity, they would have the same momentum and will deliver the same ...
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Why don't comets just vapourize away?
As far as I know, comets are in a freefall around the sun. That would mean, net acceleration due to gravity is almost zero because R =m (g-a) where R is reaction force. Now pressure is force per ...
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Calculating the power of a pneumatic piston vibrator
I am using a pneumatically-driven piston vibrator to compact a tank filled with granular material. The intensity of the vibrator can be regulated by changing the pressure of the pressurized air fed ...
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Why we consider pressure do not vary with height incase a gas in a vessel?
Why pressure do not vary with respect to height incase a gas contained in a vessel and atmospheric air pressure varies with respect to height.
for example we consider constant pressure in a mercury ...
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Why does air get trapped below water pouring into a glass?
The drinking-water-tap at my workplace has a low pressure continuous stream of water. When I pour water into a glass which has at least about (depth) 5cm of water in it, surprisingly large air bubbles ...
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Is pressure exerted by different forces on a fluid particle same? [closed]
If the closed container containing the fluid (not any air) is moving with some acceleration, can pressure due to a fluid particle's weight be equal to pressure due to a force exerted by another fluid ...
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Amplifying stress at near perfect vacuum?
So, I've got a vacuum chamber as part of a home freeze drying project. It is a cylindrical steel pot with a 1.5in acrylic lid. The manual is poorly translated from Chinese, so some of it is seemingly ...
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Physical meaning of variation of force of pressure with altitude in fluid
We usually prove that pressure is a function altitute Z. Imagine a cube in a fluid, then the force of pressure on the bottom surface is higher than the force of pressure on the top surface. But we don'...
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Does venturi effect violate pascal's law?
If we use Bernouill's law to compare pressure between point 1 and point 2, we find that P(2)gdH=0, we conclute P(2)=P(1).
I must have made a mistake but where is?
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Woodworking clamps, does force add up?
I was watching a woodworking video about glue, and the guy was clamping two pieces of wood together using a total of 8 clamps. He argued that by doing so he would apply 8 times the maximum force of ...
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