# Tagged Questions

The tag has no usage guidance.

142 views

### Double dot product in Cylindrical polar coordinates - Strain Energy

I'm working with a problem in linear elasticity, and I have to calculate the strain energy function as follows: $$2W=σ_{ij}ε_{ij}$$ Where σ and ε are symmetric rank 2 tensors. For cartesian ...
200 views

### what is the static pressure in a yield stress fluid?

Suppose I have a tank filled and there is no slip at the walls. If the tank is filled with a Newtonian fluid and is in static equilibrium, we know that the pressure is defined as $p = \rho g z$. But ...
278 views

### How wide does a wall of ice need to be to stay in place?

Let us say that we have unlimited manpower to construct a huge wall of water ice e.g. 200 m tall (700 feet). -and that the wall is placed in a climate, where the temperature never (for your purpose) ...
55 views

### Practical hardware question regarding optical source for an array of fiber bragg gratings [closed]

I have a single 1 meter array of 5 fiber bragg gratings that has FC/APC connectors on both ends. I will be embedding the array in a material and want to be able to do a quick check that the array is ...
106 views

2k views

### What causes stress concentration (aka stress risers/raisers) at corners?

I've read a few explanations about why stress concentration occurs at sharp corners but I don't find the explanations intuitive. Can anyone explain it perhaps using an analogy such as atoms "holding ...
21 views

### Estimating the fatigue life of elastomer diaphragm [duplicate]

Disclaimer: I have asked this question before, but it got put on hold because it was judged as off-topic. I happened to disagree and explained my reasons in the comments, but they have been ignored, ...
16k views

### Neutral axis of T shaped beam? [closed]

I am not a mechanics or physics student but a computer science student. I came across a question related to find neutral axis of figure but I do not have slightest idea of what it is and how to find ...
121 views

### Do all impacts create a wave-like disturbance in the medium through which they travel?

There is a scene in the first Matrix movie, where a helicopter strikes a skyscraper. The most interesting part is the 'slow-motion' bit where, as the helicopter strikes the building, a wave first ...
4k views

### Stress in a thick-walled pressure vessel

I can find many references that give the stress in the walls of a pressure vessel for spheres and tubes, but they all seem to be limited to a thin-wall approximation. I'll limit my writing here to ...
69 views

### Potential collapse during an earthquake? [closed]

I was asked to determine the shear forces on 12" diameter table legs supporting a few hundred pounds of static weight. How does one calculate or determine the potential force on the legs and/or ...
412 views

### Stress analysis of a cantilever beam using FDM

I am a CSE researcher with a not so in depth background of physics. As a part of my research in object modelling, I am trying to computationally figure out the stress for various objects by using ...
417 views

### Equivalent of the Kirsch Equations for an elliptical rather than circular hole

Is there an equivalent set of closed form equations to the Kirsch Equations but for an elliptical hole rather than a circular hole?
161 views

### Why can we analyse force balance on a dislocation?

Dislocation (like screw or edge dislocation) is not a 'real' thing, while Newton's laws only apply to a real object (no matter macroscopic, like stars, or microscopic, like atoms). In the derivation ...
263 views

### What happens when a piezo crystal is exposed to a vacuum?

Application of mechanical stress to a piezo crystal generates a charge. Quoting from wikipedia, a 1 cm3 cube of quartz with 2 kN (500 lbf) of correctly applied force can produce a voltage of 12500 ...
274 views

### Decomposition of deformation into bend, stretch and twist?

I'm wondering is there any way to decompose the deformation of an object into different components? For example, into stretching, bending and twisting part respectively? The decomposition could be ...
138 views

### Hollow stone columns provide more support?

In history class in elementary school I remember learning that the Greeks would build their stone columns hollow because they thought this provided more support. Is it true that a hollow column is ...
2k views

### What is a strain gauge and how do I use one?

As the title says, I have no idea what these things are or how to get or use one. Can I receive a simple explanation or links to one? I'm a computer engineer so I have very little physics/mechanical ...
### Why is $dL = L d\epsilon$?
Let's say there's a random elastic material. It's length is $L$ and it's tensile strain $\epsilon= (L-L_0)/L_0$ Now, when one pulls on it the following is true: \$dW_{tot}=FdL =\sigma AdL=\sigma A L ...