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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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 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 ...
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Calculating the pressure inside catenoid formed using soap film?
Soap film will not readily form a cylinder, instead, it will form a catenoid if it's circular faces are flat. I know that this happens to minimise surface area.
But how to prove that this provides the ...
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Water traveling on a letter in a water feature
Difficult for me to ask as I'm not a physicist.
Assume you have a water feature in the form of a waterfall where the water runs down a wall. On this wall, there are letters attached by a raised ...
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Necking stage in bubble detachment
The first image is the bubble dynamics in nucleate boiling, in a) you can see that the bubble is detaching by minimizing contact line with surface until zero, while in b) the bubble is enlongate and ...
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Surface tension in a bubble
In a bubble or liquid droplet how is tangential surface tension force assumed to be balanced by perpendicular pressure force?
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Surface tension [duplicate]
Does surface tension force act lateral or perpendicular to the surface of liquid .
The formula of surface tension ;
Surface tension = Force/length
What does the parameter length mean,the perimeter,...
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Strange occurrence of glue drying
What happened here? I by accident spilled super glue and formed these amazing ridge patterns. Any ideas what caused this to happen?
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In what case does the parameter of surface tension vary? [closed]
I was trying to solve a question regarding force of surface tension,it happens that I was unable to solve it using F = Tl,But it happens that the intended solution was to be done such that F =T2l,but ...
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Young Laplace Equation for Surface tension
Consider a perfectly wetting fluid of surface tension S which is the be filled inside two vessels:
A) A Cuboidal box
B)A Cylindrical vessel of radius R.
The fluid, due to surface tension rises near ...
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For a water in a beaker, is the surface tension different at center than at regions water touches the beaker?
Is the surface tension at regions touching the beaker altered as a result of adhesive forces between water and glass?
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About meniscus of combination of fluids
1st Question. Let us say we have a beaker(glass tube) of half filled water. Surely the surface of water attains a curved shape. Will this shape remain if oil is added on top of water?
2nd question. ...
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Why do some objects tend to sink after some time in water even if they float at the start?
I have observed this phenomenon in swimming pools: I have seen many dead insects floating on the surface, but after some time some they tend to sink down without any external influence. Why does this ...
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About the floatation of bodies on a surface
A body which is partially floating in water is in equilibrium due to the balancing of the buoyant force and the weight of the body. Now what will happen to a body floating on the surface of the liquid ...
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Why dont inner molecules pull the stretched soap film inwards?
Soap Film Surface Tention
When we stretch the soap film (as shown in linked video), the top and bottom surfaces(shown in blue) get stretched and hence pull back with some force that we call as the ...
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Reason for nature of surface tension
According to a high school textbook, stretching of bonds near the surface of the fluid causes a force acting on neighbouring molecules of fluid between themselves like small small 'springs' which try ...
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Why do wet napkins stick to mirrors or glass?
Take a dry piece of napkin & put it against a mirror ==> it falls down.
Dab it in water, oil, or alcohol ==> it now sticks / adheres to the mirror.
How can we explain this in physics terms? ...
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Newton ring can be used to measure the surface tension coefficient of liquid?
I don't quite understand the principle of Newton's ring. I want to know whether Newton's ring can be used to measure the surface tension coefficient of liquid
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Force on molecules near water surface [duplicate]
Here the way,origin of surface tension is explained is by considering two molecules,one near the water surface and the other in the bulk of the water. The molecule in the bulk of the water experiences ...
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Why do puddles of coffee sludge have spikes over its perimeter at regular intervals?
After I finished my coffee, I by mistake dropped my cup on the floor. The sludge as it dropped, painted circles with little spikes in gaps over it perimeter:
Why do these spikes come in (mostly) ...
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