# 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

680 questions
Filter by
Sorted by
Tagged with
31 views

### Curvature due to changes in surface tension

What happens to curvature of a surface when the surface tension starts to decrease?
20 views

### General treatment of surface tension non-relativistic classical theory

I'm reading lecture notes on fluid mechanics course, and I wrote that an algebraic definition of surface tension can be constructed from work per unit area to balance the forces along the surface. ...
23 views

### What makes silicone sticky?

I've read from 3M's Adhesion Science articles and this StackExchange question that there are three types of adhesion: chemical, physical, and electrostatic. I'm curious about what makes silicone ...
26 views

### Requesting good reference to understand the Gurtin-Murdoch model of surface elasticity

I am searching for a good and understandable reference about the Gurtin-Mordoch model for surface elasticity. I was wondering if anyone can help me with the preliminaries and good references to fully ...
13 views

### Dual-medium Plateau-Rayleigh Instability

(This is my first question here so I would really appreciate your guidance on how to use SO better!) I’ve been working on the Plateau-Rayleigh instability for some time and I was considering the ...
1 vote
42 views

### Nitro Brews and Sodas

I feel pretty sure this is a mechanics question, so here goes. I just finished a Nitro Pepsi - Yum! (I know, 63 grams of sugar. I had to brush my teeth twice after drinking it!) It is well known ...
67 views

### Confusion in Derivation of Excess Pressure in a Cylindrical Drop

I have recently learnt about surface tension and have developed a list of key points to solve problems:- Surface tension acts on the surface where a surface is defined as the interface(flat or curved)...
33 views

### Since surface tension and area are conjugate variables, is there a uncertainty relation between them? $\Delta \gamma \Delta A \geq \text{constant}$

Since all conjugate variables have uncertainty relations like ; $$\Delta f \Delta t \geq \text{constant}$$ $$\Delta \lambda \Delta x \geq \text{constant}$$ Etcetera, is there also a 'uncertainty ...
24 views

### What does a negative wetting tension $\delta F$ mean?

If a solid polymer has a drop of liquid (water) and shows a negative value of wetting tension, what does this mean? Does this mean that the drop of liquid will bead up instead of spreading on the ...
40 views

### A question about the form of Laplace law

Sometimes, I find some websites writing laplace law as: \begin{equation} p = \gamma\frac{1}{R} \end{equation} and some \begin{equation} p = \gamma\frac{2}{R} \end{equation} I can understand that the ...
35 views

### Why does surface tension on ANY body of water seems to have two discrete levels of roughness during light rain?

Here is a video of a flowing river during light rain. "This two levels of roughness" seems to occur on any body of water from a swimming pool to a large puddle in the street. Here is a ...
1 vote
42 views

### Why does the shape of water flowing down from a squared orifice looks like a chain?

Hello I'm a high school student in Taiwan. My classmate and I are doing a project about the shape of water flowing down from a squared orifice, something like this video. We wanna know is there a ...
39 views

### Pressure Difference with respect to Surface Tension

Suppose we have a drop on a flat surface of radius $R$ and volume $V$. Then by a standard force balance argument we can relate the surface tension ($\sigma$) and the pressure difference ($\Delta P$) ...
36 views

### Change in Surface Tension of Inviscid Flow

If we have a stationary fluid assumed inviscid (and hence zero viscosity), it's well known that since there are no nonzero net resultant intermolecular forces on the fluids molecules, it possess' no ...
10 views

### Surface tension plot against time when a dry surface is kept on a wet one

Today I noticed an interesting phenomena, I kept a tea cup on a wet tea plate for long. When I picked up the cup again, it seemed like the plate was glued to the cup. By physical force, I seperated ...
2k views

### Are water molecules at the surface closer or farther apart than the molecules inside?

My lecturer says that since the energy of the molecules on the surface is higher (less negative), then at equilibrium there will be less molecules on the surface, hence the molecules on the surface ...
37 views

### Surface tension force between two wet objects

I have a problem related to surface tension. I hope someone good at physics can help me. The picture attached shows the two cases. I have an elastomeric sphere filled with air (compressible) and a ...
27 views

### Capillary and laplace pressure

How do I understand the difference between capillary and laplace pressures in the context of liquid interfaces?
1 vote
37 views

### Getting particles to sink and stay in solution

I'm working on a project that involves finding moving particles in a solution (in my case, a syringe, or vial). The goal is to identify particles as small as 125um(micrometers), but the problem I face ...
1 vote
44 views

### Having trouble understanding Re-derivation of Young’s Equation

I was going over a section 2.1 of this article (regarding Young's Equation and for some reason I wasn't able to derive E10 from E9 (see image below). I know it is more about the trigonometry of the ...
21 views

### Ability of some porous solids to tentatively sit on water for a while before sinking

How does a porous solid such as the cereal "Wheatena" manage to tentatively sit on water for a while before sinking? I assume it initially somehow evades capillary action, perhaps through ...
1 vote
76 views

### Whats the fault in the logic I am thinking for not balancing of a needle and any blade etc. on water?

As we know that contact angle of water with any surface is approximately zero, so why a blade or a needle floats on water as such surface tension can only provide force parallel to the water surface ...
41 views

### Why does double edge razor blade not sinks but single edge razor blade sinks in water?

We often see that we can make a double edge razor float on water due to surface tension acting at some angle on all four sides to balance the weight i got this part , but when a single edge razor ...
24 views

### Surface tension and generalization of Laplace equation of a water droplet

The shape of a semi-spherical water droplet of radius R is given by Laplace law: \begin{equation} \Delta P=\frac{2\sigma}{R} \end{equation} I know the general Laplace equation is given by: \begin{...
38 views

1 vote
41 views

### What is this liquid flow behavior called?

Every morning, when I take a clean, dry metal tumbler and fill it with hot coffee, the first sip is always different than the rest that follow. The first sip requires some coaxing, for me to tip the ...