Stress Definition and 1000 Threads

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I was initially curious by the fact that streamlines around a circle appear the same as the lines of stress around a hole: I understand that streamlines are the contour lines of the stream function ##\psi## which satisfies the Laplace equation. I was wondering there is a related function for...

Hi all, i need Permissible stress (Shear & Bending) values of various materials that is used for shaft design, as like below. Is there any software or excel sheet. kindly let know.

I know the out of plane bending stress equation for a curved I beam but I am trying to figure out where it came from. sigmaR = tFlange * sigmaNormal/(radius of curvature)

$$\text{stress}=\frac{7500\times9.8}{0.105^2\pi}\approx2.1\times10^6\,Pa$$ ##Y=20\times10^{10}\,Pa## for steel. $$\frac{\Delta L}{L}=\frac{\text{stress}}{Y}\approx1.1\times10^{-5}$$ $$\Delta L\approx2.3\times10^{-5}\,m$$

A chimney has a rectangular cross-section with external dimensions 800 × 600 mm and wall thickness 150 mm. It is 5 m high. The density of the material is 2000 kg/m3. Assuming that the material is elastic, calculate the maximum uniform wind-pressure loading (N/m2) that...

So I mixed Stratego and Chess. How? Step 1. Take a chess board and an amount of opposing stratego pieces equal to the usual chesss setup. Step 2: Make or find stickers to put behind the stratego pieces that ID them as chess pieces, at least to you. The other player will have to make educated...

The stress energy tensor has many forms based on the type of matter you are describing, dust, fluid, perfect fluid... is it true that the trace of all of these matter situations is invariant?

As all attempts to get it right but without success this is one of the problems with my workout . Where i did wrong calculations ? The questions got the answers in brackets.

Watching the Australian Open and they use a heat stress rating to protect the players. I've searched for the details of how it is calculated without success. Anyone know the formula that they use? Just curious.

hello, I'm new to this forum and I'm looking for some much needed help/guidance as i have absolutely no idea on how to workout my assignment! any help would be much appreciated

Hi, I would like to know what are all the possible causes of thermal stress. The most common are external constraints that block thermal expansion/contraction (for example a bar fixed at both ends). However I know that there are also at least two additional causes of thermal stress and that...

Hi, The context for my question is: A thin plate, which lies in the x-y plane, contains a small hole of radius a . Consider a polar co-ordinate system r,􏰆 with its origin at the centre of the hole and 􏰆defined as the angle that a radial line makes with the x-axis. A uniform uniaxial tensile...

Hello all I was wondering if anyone could figure out the what the equation below means, specifically the W term? The equation to calculate bending stress for a cross section that i have used and i know is correct is:- Bending Stress = Moment (M) * Distance From Neutral Axis (Z) / Second...

A steel bar 6.00 m long and with rectangular cross section of 5.00 cm x 2.50 cm supports a mass of 2000 kg. How much is the bar stretched ? (the young s modulus of steel is 20 x 10 n\m squared)

Hello all I am trying to calculate the bending stress of a simply supported beam with a load of 12kn at the middle of a 6m span, member depth of 0.016m I have drawn both the bending moment and shear force diagram. I want to know the following:- 1) When calculating the bending stress would...

Hi guys. Recently I've been assigned to know / calculate the capacity of the racks in our section. Our racks has layered steel pipes that are carrying the loads. After actual testing it can carry a load around 25 tons after yielding or having a bend. So my next step was to calculate for its...

I've been giving this some thought. It's clear that the stiffners will increase the resistance of the material so that the energy release is no longer high enough to cause further fracture. I'm just not sure what formula I can use to take into account the new resistance. I suspect part 1 of the...

The question is partially taken from Griffith's book. I am confused about the physical meaning of momentum in fields. I have determined the solution and found that in part d the momentum crossing the x-y plane is some value in the positive z direction. I don't however understand the physical...

Good evening everybody. This is my suggestion for answer. The tensor is diagonal and the compression is a plane stress equilibre equation div(σ)=0 so: So, does that means that = f(y.z) = Ay+Bz and =f(x.z)= Cx+Dz A,B,C and D are constants. Is that what the question meant? Thank you in...

I know that shear stress in horizontal beams has a parabolic distribution, so that the max shear stress occurs at the neutral axis. I also understand that for a beam subject to a distributed load with supports at its ends, the magnitude of the shear force is highest at the left and right ends of...

Summary: I am not a physics student but I really need to prove that aluminium will not deform 10m underwater Hi I am doing a project of a product which will sink underwater. It will be a sealed cylindrical vessel, length 2m, width 1m, thickness 0.02m. Aluminium 6061t will be used with a yield...

I'm working through the equations and I have a lot of information missing. I have calculated the longitudinal strain to be 0.4mm (4/90) is the lateral strain directly proportional to the longitudinal strain? As I need to work out poisson's ratio in order to calculate Bulk modulus, then youngs...

Hi All. Given that we may write And that the Stress-Energy Tensor of a Scalar Field may be written as; These two Equations seem to have a similar form. Is this what would be expected or is it just coincidence? Thanks in advance

Does anyone know of a set of invariants for the stress energy tensor? In particular, I would like to know if there is a small set of linearly independent invariants, each of which (or at least some of which) have a clear physical meaning.

If you have a pin tied to a string carrying a stone in the wall. And you put epoxy to the stone and wall attaching them. How is the stress transferred from the pin to the interface between stone and wall? What method is used to model the transfer function?

If I were to have a theoretical car with 4 motors controlling the 4 wheels(each with a radius of 5 in and a width of 1 in) and the car was 100 pounds, how much stress would be exerted back on to each motor?

What's really the difference between pressure and normal stress? Also I know pressure acts normal to a surface from the outside Do normal stress acts from inside? I'm reading bird transport phenomena and this is confusing

Summary: In terms of stress, strain & deformation, what is better for a given component. 1) low stress or high stress 2) less strain or large strain 3) less deformation or large deformation? Some dimensional changes were made in an existing component to study how these changes effect the...

what does it mean that fluid cannot sustain a force that is tangential to its surface.which surface fluids's surface or container? and what does it mean it cannot withstand shearing stress.what's shearing stress and what does it mean here.and why exert force only in direction perpendicular to...

Summary: I have trouble to define the y distance in my coordinatesystem I need to find an expression for the shear stress on the I figure, where the green parabola illustrates the function. I made a cut, where I defined the length from the start of figure I to the cut as z1. The formula for...

In both designs, a PVC pipe is being bent 90 degrees, fixed at each end. In both designs, the pipe is fixed at both ends. In both designs, the pipe is 1" (inner diameter) Schedule 40 PVC pipe, 450 PSI. Material code PVC 1120. NSF pw-G ASTM D1785 PPFA 02199101H6BX 0934. In design A, the length of...

I’m designing a subsea sensor that will go to a max depth of 600 m (6 MPa/60 bar). In a simple model, it will be made of a pressure housing cylinder and two end caps, all grade 5 titanium. Some geometry is attached. I’m looking for advice on how to calculate the thickness of the...

You're on Earth. You throw a ball and watch its trajectory. It's curved. That's because the Earth is curving space-time at every point along the trajectory. But the Earth itself is not present along the trajectory - there is no matter along the trajectory (let's ignore the air and any radiation...

I've attached a photo of a "problem". How would you calculate the stress at the area in question? I seriously doubt that the bending stress would vary linearly throughout the whole meter of total length of the section. I would expect it to become zero long before it reaches the opposite...

If I can determine the weight of that heavy object placed on the plank, I will be able to determine the stretch of that wire. But, when using the second condition for static equilibrium (torques of the system equal to 0), I always end up with two unknowns, no matter what point of rotation I...

Given, ##2A_P = A_Q## (cross-sections) ... (1) and, ##Y_P = 2Y_Q## ... (2) We have ##\frac {Y_P * x}{\Delta L} = \frac{Y_Q (L-x)}{\Delta L}## Using (2) in the above expression we get ##x = L/3## whereas the correct answer is ##x = 2L/3## I feel my initial idea is flawed, and that I am...

I am trying to find the correct formula for the electromagnetic stress energy tensor with the sign convention of (-, +, +, +). Is it (from Ben Cromwell at Fullerton College): $$T^{\mu \nu} = \frac{1}{\mu_0}(F^{\mu \alpha}F^{\nu}{}_{\alpha} - \frac{1}{4}g^{\mu\nu}F_{\alpha\beta}F^{\alpha...

Similarly the paper by @buchert and @ehlers https://arxiv.org/abs/astro-ph/9510056 Here the author has defined ##v_{ij}=\frac{\partial v_i}{\partial x_j}=\frac{1}{2}(\frac{\partial v_i}{\partial x_j}+\frac{\partial v_j}{\partial x_i})+\frac{1}{2}((\frac{\partial v_i}{\partial...

i really can't understand the answer of this question, is the question 1.3 in fluid mechanics by Frank ,M White For the triangular element in Fig P1.3, show that a tilted free liquid surface, in contact with an atmosphere at pressure pa, must undergo shear stress and hence begin to flow. i...

The elecromagnetic force can be expressed using the Maxwell Stress Tensor as: $$\vec F = \oint_{s} \vec T \cdot d \vec a - \epsilon \mu \frac{\partial }{\partial t} \oint_{V} \vec S d\tau $$ (How can I make the double arrow for the stress tensor ##T##?) In the static case, the second term...

Hi again, I want to know, what are the effects that stress has on the human body when it comes to work or a job? The reason I am asking this is because I plan to have a job in the future that gives me good stress and to avoid working at a job that gives me bad stress. I base this on some website...

I am really stuck on part a. For part b: strain x = (1/19*10^9)(137000+.36*95000) strain y =(1/19*10^9)(-95000-.36*137000) Is this right? For part c: sigma xx'=(sigma x+sigma y)/2+(sigma x -sigma y)cos(2*28)/2+sigma xy sin(s*28) sigma yy'=(sigma x+sigma y)/2-(sigma x -sigma y)cos(2*28)/2-sigma...

So I got a is elongation. For part b and d, I am unsure where to start. For c, i got compression and for e, I put that the dotted line is the red block

I am really just totally stuck. I think you need to find force being applied onto the rod but I cannot figure that out

Hello, I need to input the bending stress from a database I am not sure what name it is, would it be yield strength or tensile strength? thanks

Hi, Starting with an example to clarify what I am looking for. Assume an extension force applied on a distance from the centroid/neutral axis of a body: see attached, please. As result, bending force besides the tensile force will be generated in that body as presented in section A-A in the...

Homework Statement Here's a snapshot of the problem: Homework Equations + Newton's 2nd Law. The Attempt at a Solution My question is: why does the delta P term have only a single 40 kN force considered, whereas for delta EF there's an F/2? Thanks for your time.

Can someone tell me a theory in which the lowest twist operators are not the stress tensor and its derivatives? My aim is to work out the lightcone OPE for the theory and derive bounds like the averaged null energy condition. (as worked out in https://arxiv.org/pdf/1610.05308.pdf)