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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If the surface tension is reduced to half(say by using a surfactant), what would be the effect on the size of an air bubble in the liquid

If I reduce the surface tension to half of the original value, what would be the effect on the size of an air bubble in the fluid? What would be the effect on buoyancy and drag forces? Also, if I ...
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25 views

Why does surface tension of water-ethanol binary mixture decrease with increasing concentration of ethanol?

I was thinking that it must be due to weaker hydrogen bonding in ethanol than in water. But then I learnt that Raman Spectroscopy and viscosity measurements suggest that upto a certain ethanol ...
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100 views

Can a fruit fly move through a large bubble without popping it?

Assume what logistics you need to in order for something like this to be possible. Can a fruit fly move through a large bubble without popping it?
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Application of surface tension in thermodynamics [closed]

I'm writing a paper about surface tension, and have problems with finding literature about application of surface tension in measuring some thermodynamics quantities. Can you help me? Thank you
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61 views

Why is raindrop spherical in shape? [duplicate]

As the topic suggests why the raindrop is spherical in shape? Why it is not triangular or bipyramidal or tetrahedral? Is centre of mass or density of water related to it?
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When drying paint brushes washed with water, which way is the best to orient them?

After washing my paint brushes with soap and water and rinsing them, in order to avoid damage to the bristles and the ferrules and the wooden handle, is it best to hang them bristles down and let ...
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Finding Surface Tension of water at certain Temperature and Pressure

The question is: Using the Young-Laplace Equation (if applicable), find the surface tension (dynes/cm) for water at 20 degrees Celsius with 2.5 psi. Round to the nearest tenth. ...
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triangular symmetry of surface tension configuration of small grains on water

This is freshly ground pepper on water. Why is there a triangular configuration of the water around the pepper fragment? Surely all these pepper fragments have different shapes? You can clearly see ...
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55 views

Is there surface tension between a solid and a liquid?

The molecules of a solid are so tightly bound together that they are fixed in position unlike in a liquid or gas where they may move freely. In that case it seems like the surface tension between the ...
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33 views

Does buoyancy change on smaller scales?

For baseball size objects on the order of centimeters across we have experience with what floats and what doesn't. A stick will float and a rock will not. But what if the rock were a grain of sand? ...
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Why does a pitcher with lemon juice have foam, while one with pure water does not?

Whenever I pour water into lemon juice (pouring directly from the tap into the pitcher, not quietly along its edge) I get a foam on top: The same pitcher with water (same water tap, pitcher, time ...
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54 views

What is the cause of the surface tension of the liquids? [duplicate]

What is the cause of the surface tension of the liquids? How to know the direction of tension force on the free surface of the liquid? I know that the surface tension is the force acting normally ...
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Can a liquid in a tube have a contact angle of 0 or 180 degrees with the tube?

When a liquid is placed in a tube, it makes contact with the solid walls and has a contact angle (the angle between the tangent to the liquid surface and the wall). What does it mean for the contact ...
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When metal solidified, why is its surface not flat like polished?

I expect that what one can see on the outside of a just solidified piece of metal is just the "raw" surface of the inner stucture. Solidifying metals or alloys arranges in partial christal latices ...
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Is surface tension the result of a pressure drop over the air-water interface or visa versa, for a two sphere system?

For a liquid bridge between two spheres the Young-Laplace equation states that: $\vartriangle p= \gamma\bigl(\frac{1}{R_1}+\frac{1}{R_2}\bigr)$ where $\vartriangle p$ is the capillary pressure ...
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150 views

Difference in electrons excitation in Au (111) between perpendicular and diagonal orientation?

In Au (111) single crystalline as shown in attached file, is there a difference the way electrons are excited when they are excited from perpendicular and diagonal orientation as shown in the figure ...
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Why does water sometimes form bubbles when I pour it into a glass?

Sometimes when I'm filling up a container with water from the tap, bubbles will form on the top of the water. They look a little like soap sud bubbles, but there's no soap suds present. I notice, ...
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Does wetting of fabric surfaces depend on the microscopic surface structure?

I am trying to coat a polymer fabric with a metal alloy by dipping it into the molten metal. (For example a polyamide like Nylon in eutectic Bi/Sn alloy at 138°C , as in Wetting the surface for ...
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Wetting the surface for soaking Nylon fabric in metal

I'm trying to create metal covered lace. My sister would use it as an artistic material. An interesting material A relevant point is that the mechanical rigidity of the metal is used, so it is not ...
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3answers
142 views

Size of a glass capillary for noticable capillary action

How big would a glass capillary have to be to have noticable capillary action? Also, does capillary action happen in plastic tubes?
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Meniscus attached to an inclined plate

To be more specific, suppose a hydrophilic infinite plate is stuck into a semi-infinite region of water, above the water is a semi-infinite region of air, when the plate is stuck into the water ...
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74 views

How does this capillary-action setup not become a perpetual motion machine?

If you have a very thin glass tube and you place it into water, let's say the water in the tube rises to the height of $x$ mm from the surface of the water. What would happen if you poked a hole in ...
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36 views

The shape of a bubble? [duplicate]

I have always wondered about a shape of a soap bubble. Why is it always spherical and not some other shape (like, cylindrical)? And why are the layers of the soap bubbles so thin? Also when someone ...
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Calculation of tension in a loop with force acting outwards

I'm having a few problems with understanding how to calculate tension in a loop. If I have a circular loop, and some force is applied uniformly radially outwards in such a way that the force acting ...
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276 views

Capillary action meniscus height in a tube fitted inside another tube?

I was thinking about how would capillary action change in a tube (classic example) and in a tube fitted inside another tube (considering water as the liquid involved). Height of liquid column: ...
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Does the value of Surface tension (the value of the constant) change with a change in surface area?

Surface Tension or ϒ (as in gamma) is a constant value for a particular fluid in fixed conditions. When we increase the surface area of the interface, more molecules pop up at the surface and ...
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Fluid flowing into small pores

I have some open porous foams with pore sizes ranging from 50-100nm. I want to flow water into this structure but even at 30 atmospheres it would NOT go in. I am looking for a way to calculate the ...
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Wavy stream of liquid

When pouring a liquid into a glass some streams have a wavy shape, like the one in the following photo: (Couldn't find a better picture, sorry.) What causes the stream to be of such a shape?
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Why does water pouring from a glass sometimes travel down the side of the glass?

If you have a glass of water, say, three quarters full and you pour it at an angle of say, $45^{\circ}$ with respect to the the table, the water comes out of the glass and goes directly down towards ...
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Why pouring milk from a height makes a chain shape? [duplicate]

I have noticed a chain-like shape when milk is poured from a height into a cup. Actually the chain pattern repeats itself after some distance and again till it reaches the milk in the cup. Any ...
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How to find the maximum area of a slot that can keep water in a trough by surface tension?

Assume I have a trough of water 5mm deep. If I cut a slot (oval) into that trough what is the maximum size/area (length x width) that slot can be without leaking? This question is similar to Max. ...
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Does the contact angle of a drop depend theoretically on the size of the drop?

According to Wikipedia, contact angle depends on the hydrophobicity of the surface and on thermodynamic equilibrium. But how does it in theory depend on the drop size? In other words, how would a ...
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364 views

Water evaporation

It is known that molecules at the surface are strongly attached to each other (more attraction less repulsion) than those within the bulk attraction and repulsion are balanced). This is the molecular ...
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physics of wet hair

I'm curious about the physics behind the clumping of wet hair. More specifically, how the amount of water in hair and distance between hairs affect the clumping process. I know intuitively that when ...
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Thermodynamic quantities of thin soap film on wire frame

Here is a question I am trying to solve. Sorry for the highlighting, it is not relevant. Here are my answers. For a), I would write $dE = dQ + dW$, following the first principle of thermodynamics. ...
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181 views

Why can liquid mercury sit on salt?

A video shows liquid mercury sitting on top of table salt. Even though the mercury is much denser, it does not sink to the bottom. Why does this happen? Is the mercury just so thick that it is like ...
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About an upside down cup of water against atmosphere pressure

There is an experiment we learned from high school that demonstrated how atmosphere pressure worked. Fill a cup of water and put a cardboard on top of it, then turn it upside-down, the water will not ...
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What is the maximum net force of surface tension per gram of water?

I've always wondered how much force water exerted through surface tension. By maximum I mean the theoretical pulling/attracting power. Also, what would happen if you raised or lowered the power? ...
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Change in radius of a charged bubble

I was thinking about what'd happen to the radius of a bubble, if a charge is uniformly distributed over it. At the beginning, I thought that the bubble would expand, for sure, because of the ...
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146 views

Foam patterns on espresso

When just prepared, an espresso has a thin layer of foam, known as crema, on its surface. As I move my drink from the bar to a table, the motion destroys the homogeneity of the layer, but I've noticed ...
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How does surface tension enable insects to walk on water?

I understand that water molecules at the surface have a net inward attraction due to the lack of water molecules above them. I've been reading a bunch of articles, and they say that this inward pull ...
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Why is the pressure inside a soap bubble higher than outside?

Apparently, the air inside a soap bubble is under higher pressure than the surrounding air. This is for instance apparent in the sound bubbles make when they burst. Why is the pressure inside the ...
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132 views

Rate of Dripping of tube

My original problem was to discover the rate at which leaking taps dripped, and its relation with the tap's size, radius, etc. However, I have no clue how taps work, so I simplified the problem. ...
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Walking on water

I was wondering about walking on water. I wonder if we can use surface tension to do this. Lets say I make a pair of shoes in shape which has infinite perimeter (e.g a koch snowflake) with glass. Now ...
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Capillary tube of insufficient length

I was wondering if we have a very thin glass tube placed in a tub of liquid and the portion of the tube outside the liquid is lesser than the height to which the liquid can rise because of ...
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4answers
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Negative pressure, tension, and energy conditions

We have lots of common everyday experience with positive pressure, the canonical example is a gas. But other examples of positive pressure are easy to imagine: for instance, a solid that gets ...
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36 views

Internal energy given surface tension

Could anyone offer some insight for the following problem: The internal energy and the entropy are proportional to the area. Show that the internal energy per area is given by $$u(T) = \frac{U}{A} = ...
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256 views

What could be added to tap water to reduce air bubble formation on a submerged object?

Submerge your hand in a bucket of water. Some air bubbles appear immediately and others add to the surface of the hand over time. Is there anything that could be added to the water to reduce the ...
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A cup of water in ZERO gravity

What will happen if I try to pour a cup of water in zero gravity, into another empty cup? Will the water come out of the cup? The adhesive force between the water molecules and the interior of the cup ...
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Can we break surface tension without physical contact?

It's my understanding that surface tension is caused by hydrogen bonding. My question is whether or not we can break that bond, without physical contact. Could we use electricity, light, heat, or ...