Questions tagged [surface-tension]
Surface tension occurs due to the tendency of liquid molecules to favor their own kind. Surface tension is important in fluid multiphase systems typically at small length and velocity
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Surface Tension vs. Gravity: Finding the Critical Length Scale
I'm studying Kardar's "Statistical mechanics of particles" book and tackled a problem. After solving it, I checked Kardar's solution and found that he has different approach. I'm interested ...
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Regarding angle of contact and capillary tube of insufficient length
It is written in my book that when a capillary tube is of insufficient length, the liquid does not overflow and the shape of the liquid meniscus changes, but the angle of contact remains the same. I ...
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Question on fluid jet profile in the limit of zero surface tension
While reading on the Plateau Rayleigh instability of fluid jets, the following thought came to my mind: suppose we have a fluid jet with zero cohesion forces (and therefore zero surface tension) ...
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Is there an intrinsic energy-momentum associated with constraining forces that don't do work?
As an example, consider a continuous charge distribution, within Maxwell's model of classical electrodynamics, that is brought from infinity onto a spherical surface at a radius $r$ from the origin. ...
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How does a bubble pop?
I was looking at some old slow motion videos showing a phenomenon where a bubble is popped by firing a sphere (or pea) through it.
One obvious thing that happens is that the pea does not pop the ...
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Soap film retraction dynamics
Let’s say you have a planar soap film, which thickness increases linearly. If you burst it, the film will retrace and the retracing speed will decrease. How exactly does the velocity of bursting ...
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Surface tension versus stress in a balloon's membrane
I am conducting an experiment in which I am measuring how the internal pressure in a balloon varies with its circumference. To explain the relationship (shown in the graph below) I decided to ...
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How does pressure exist inside a drop of water?
Consider pressure inside a drop of water. I have seen a formula for it where
$$\text{Pressure Inside}=\text{Pressure Outside}+2\frac{S}{R}.$$
I want to know how pressure exists inside the liquid. Is ...
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Why does curvature reduce the inward attractive force of molecules?
This question concerns the first 2 paragraphs of this text.
I am struggling to visualize why molecules on the flat surface experience more net inward force than those on a curved surface. If we have 2 ...
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Measuring the tension of a drumhead
I'm working on an experiment to see how the tension of a drumhead impacts the frequency of its sound, but I'm not sure as to how I could measure this.
I found this forum thread from 2012, which ...
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How are curved soap films stable?
How do curved soap films remain in equilibrium, if surface tension tries to pull them taut?
What I understand:
Surface tension acts tangentially on a surface.
The potential is energy is proportional ...
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Surface Tension On The Surfaces which are not exposed to Environment
In the picture Below, I was asked to Calculate the force due to surface tension on the left side of the water about an imaginary square ABCD by the right side of water. ($T$ = surface Tenson)
One has ...
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Can a soap film be expanded infinitely?
Consider a rectangular wire frame with a sliding wire of length l. When the frame is dipped in soap solution, a soap film is formed over it. Assume that there is no friction between the arms and the ...
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In physics, when should one use and not use calculus?
Assume that a drop of liquid evaporates by decrease in its surface energy, so that its temperature remains unchanged. What should be the minimum radius of the drop for this to be possible? The surface ...
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Why does surface tension increase on addition of soluble impurities?
I read that addition of soluble impurities increase the surface tension of water. I initially thought it was because when soluble impurities dissolve in water it leads to the dissociation of that ...
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Why do hot water droplets persist in cooler water?
I notice this phenomenon typically when mixing hot or warm water with cold water. Basically, tiny droplets of hot water travel inside the body of cooler water and persist. I have included a photo of ...
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Liquid Vapour Surface Tension Interaction with Solid
In my book there's an experiment to calculate the value of surface tension in which a solid of certain weight is kept on the surface of a liquid and it remains in equilibrium . Now the book states ...
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Could a fish swim out of a sphere of water in a zero-gravity environment?
Can a fish swim out of a sphere of water in a zero-gravity environment?
I am going to state some assumptions.
We assume the sphere of water is not affected by any thermal properties of its zero-...
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Marangoni effect and surface tension gradients in binary liquid
I have a question regarding the understanding of the Marangoni effect. A simple visualization is the deposition of a drop of soap (some surfactant-laden solution) into pure water. Because the soap ...
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Same needle shows Hydrophobic and hydrophilic behaviour just by changing orientation or position (from surface to bulk)
If I penetrate water's surface with needle (using hand) then Cohesive forces> Adhesive forces and water molecules climb up the needle (exactly like capillary action) and needle behaves ...
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Shape of a static capillary surface
I am studying the effects of surface tension and in particular the shape of a capillary interface in hydrostatic condition.
Let's recall the Young-Laplace Equation
$ \Delta P = \sigma \bigg(\frac{1}{...
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Homemade Du Nüoy ring?
I am helping my daughter work on her science project. She wants to test the surface tension of various solutions.
I bought a cheap tensiometer off of Amazon and now I need the Du Nüoy ring to attach ...
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Height of a stable droplet on a perfectly wetting surface, shape of a water drop
I would like to clarify that this is not a homework question, but a problem that I chose to want to solve to satisfy my curiosity. I would like to understand whether the physical concepts I have ...
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Why do water particles appear to be exiting a stream of water from a faucet, instead of the stream being held together by surface tension?
I recently noticed an interesting phenomenon while watching the tap running in my kitchen. At the time, there was bright sunlight coming in the kitchen window. As the stream was running out of the tap ...
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How would the volume of a drop of water (from a dropper) on the Moon and other bodies compare to one on Earth? (indoors of course!)
Searching for "volume of a drop of water from an eyedropper", I ran across this answer on Quora:
It depends on the size of the dispensing tip, but generally for a Pasteur pipette it is ...
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How are bubbles formed when a raindrop hits a flat pool of water?
I have noticed that raindrop impact can create a bubble on the surface of the water in a hot tub (104°F) up to several centimeters in diameter that is stable for several seconds before bursting.
The ...
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How dose the surface area of a fiber change , when in situ surface modification is occured?
I in situ modified the surface of a fiber which is inside water to more hydrophobic. Density of fiber decreased. How I explain it using surface energy and tension?
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Context: Surface tension. Is the interface more dense than the bulk? [duplicate]
Considering, the phenomenon of surface tension, is the interface of the liquid more dense than the bulk phase? Considering, if it were more dense, the phenomenon of surface tension would be explained, ...
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Is the force of surface tension acting on a liquid mensicus in a capillary tube an internal force for the surface?
When we calculate the excess pressure on the concave side of the meniscus of the liquid surface formed in a capillary tube, we balance the force by the atmospheric pressure, force by the pressure on ...
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Why is there excess pressure on the concave side of liquid meniscus in a capillary tube?
I understand the derivation for the expression of excess pressure inside a liquid drop, but, most books also use this concept of excess pressure for explaining the rise of liquid column inside a ...
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Should we regard a capillary tube as a source of potential energy?
When a capillary tube is inserted into a large body of water, there is an increase in potential energy (PE) of the system. This is because the increase in PE of the rising water in the capillary is ...
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Contact Angle acid-base approach negative square root
I've collected Contact Angles for 3 different liquids (ethylene glycol, glycerol, and water) on a substrate. My aim is to use the acid-base approach (eq. below) to obtain the dispersion, acid, and ...
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Why fibers go to the liquid/liquid interface instead of staying in the bulk phase?
I have an ionic liquid solution phase and an organic phase. They are immiscible. When I place a small piece of nylon fibre in the liquid it always goes to the liquid/liquid interface instead of ...
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Gravity vs adhesion of a water droplet
How much volume can a water droplet that is attached to a vertical glass surface have before it begins to roll downwards?
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Breaking apart the surface tension of a water droplet
How far apart do two vertical glass surfaces have to stand for a water droplet that is sticking to both of them to break into two?
I apologize in advance for the question possibly being too imprecise �...
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What is the entropy variation when drying a wet surface with an absorbent cloth?
A mass of water on a surface is considered as a hydrostatic thermodynamic system. It seems reasonable to assume that the internal energy of this system $U(S,V,A)$ depends on the entropy, the volume ...
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Why do dry lentils cluster around air bubbles?
When I pour dry lentils into a water bowl, I notice many of them form little clusters, with an air bubble in the center.
Why does this happen? I'm guessing something about static electricity. But not ...
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Droplet Breakup model solely for charged droplets in electric field?
At the moment I am trying to simulate charged droplets and their berakup in an homogeneous electrical field in vacuum. I am using a VoF-Method, but as the droplets get smaller and smaller I would need ...
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Why does water come out of a bottle in waves?
So imagine you have a bottle of water or any type of liquid (like a bottle of milk that has just been opened)that is completely full or even three quarter of it is full,why does the water or milk come ...
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Value for the interfacial tension and surface energy of stainless steel
I measured in an experiment the contact angle of stainless steel with 3 different liquids (water, glycerol and ethylene glycol). Through a fit with the 'Equation of State' from Neumann I obtained an ...
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Why does capillary effect occur? [duplicate]
It is seen that water moves up in cases as given in the image. What causes this action?
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Water Droplet on solid plate (Young's Equation via Force Analysis)
I was reading about Solid-Liquid-Air Interfaces pg 484 in Competitive Physics Volume 1 by Wang and Ricardo and we were proving Young's equation regarding the contact angle of the water droplet on this ...
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How does the size of a water drop varies between materials?
Say you have rising steam forming water on some surface and when the water accumulates, it forms a drop that falls because of (I suppose? Not sure) Mass exceeding the force of surface tension.
Does ...
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Why dows Water in the shower run down glass pane in meanders?
The last days I noticed that after taking a shower (cabin has glass walls, safety glass if it matters) and finally splashing the glass panes for cleaning soap residues off, some of the remaining water ...
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Why does it take energy to grow the surface of a drop?
Classical nucleation theory predicts that the growth of small nuclei is thermodynamically disfavoured, on account of the energy required to grow its surface. I am struggling to understand why it takes ...
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Meniscus of water after breaking the capillary
Let us take the capillary dipped in water and we let the water climb normally till its maximum height. Now we break the capillary (assume clean cleavage so there aren't any rough surfaces produced) at ...
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How to prove that a drop of water in the weightlessness of space is round in shape?
How to prove that a drop of water in the weightlessness of space is round in shape theoretically? More specifically, how to prove that a drop of water in the weightlessness of space is round in ...
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Why is it faster to swim under water than on the surface?
In competitive swimming, swimmers are allowed to swim first 15 meters completely submerged, and it seems that they can swim much faster that way than if they swim on the surface.
I've seen several ...
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When a balloon rises, the outside pressure decreases with altitude, does the pressure inside the balloon decrease accordingly?
When the balloon rises and the pressure on its outer surface decreases, does the inner pressure also decrease? If Boyle's law holds true in this case, then the pressure of the gas inside the balloon ...
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Why is the surface tension of copper and cadmium in molten state increases with increase in temperature while it decrease for other liquids?
Recently, I saw a question in my exam regarding surface tension. It was mentioned in the answer key that the surface tension of copper and cadmium in the molten state increases with an increase in ...