Stress Definition and 1000 Threads

1)In a flowing fluid in laminar fashion we know that it flows in planes which slides over each other, Let's take a fluid element (cylindrical) in a pipe(Radius=R) the resistive force is (stress)(cross section area of cylinder with radius 'r') acting in backward direction, now if I take Flow...

In superconducting state, If the superconductor and the guide line are stationary, will the force between the the guide line and the superconductor change when they are close to or far away from the magnet?

I am trying to determine a normal stress balance at an axisymmetric and dynamic fluid-fluid interface, ##z(r,t)##. For a static, free surface, this simplifies to the Young-Laplace equation: $$ \Delta p=\rho gz-\sigma2H=\rho gz-\frac{\sigma}{r}\frac{\partial}{\partial r}\left(r\frac{\partial...

Hello! I was talking with a friend today about electrical motors and we started talking about theoretical designs. One question came up which was could the Maxwell Stress Tensor be used to calculate the torque on a rotor of a motor where the airgap is held constant and the magnetic circuit...

The scenario is: we have a simply supported beam, with the supports being an arbitrary distance inward from the outer edge of the beam (both are the same distance from their edges such that the beam is symmetrical about its centre). The beam also experiences uniform loading across the entirety...

Hi, just wanted to ask for the von Mises criterion equation, is the equation without the SF (the one I circled in blue) only applicable when yielding has FIRST occurred? (i.e when SF=1)? and is the equation including the SF (one I circled in orange) applicable to all cases? (i.e whether the...

Homework Statement .[/B] For a certain type of steel, stress is always proportional to strain with Young's modulus 20 x 10^10 N/m^2. The steel has density 7.86 x 10^3 kg/m^3. A rod 80.0 cm long, made of this steel, is fired at 12.0 m/s straight at a very hard wall. a) The speed of a...

Hi, there's no particular question I need help on - just a few things I need clarifying. To determine the max shear stress, I know max shear stress = (max normal stress - min normal stress)/2, but are these equations true for a 3D stress state? (please look at attached image) Thank you

How to find the angular speed, on which a spinning hollow cylindrical body breaks due to inertial stress(force)? I found 2 sources(http://www.roymech.co.uk/Useful_Tables/Cams_Springs/Flywheels.html (last 2 equations) ...

Homework Statement Homework Equations ΔL=LαΔT σ=EΔL/L The Attempt at a Solution For part a, I used the coefficient of linear expansion for copper and the change in temperature to find the change in length (0.068%). I thought part b had the same answer. The two are attached, and I would...

Homework Statement A titanium disk (with ##E=107 ~GPa##, Poisson's ratio, ##v=0.34##) precisely ##l_0=8~mm## thick by ##d_0=30~mm## diameter is used as a cover plate in a mechanical loading device. If a ##P=20~kN## load is applied to the disk, calculate the resulting dimensions, ##l_{01}## and...

1. In my materials science's exam, I had the following question: What would be the maximum force F to cause failure in a block that has been drilled at two place? See following drawing: (Lame paint skills, I know..) 2. Homework Equations 1) D/W 2) σ = F/S The Attempt at a Solution 1)First...

Homework Statement A 30kg pallet falls from a height of 2m onto a protective cover. The cover has an area of 269m² and an overall thickness of 10.9mm. a. What is the force/pressure on the cover? b. What is the bending stress on the cover? Homework Equations F=ma bending stress =...

How do we know that the stress tensor must be symmetric in the Navier-Stokes equation? Here are some papers that discuss this issue beyond the usual derivations: Behavior of a Vorticity Influenced Asymmetric Stress Tensor In Fluid Flow http://www.dtic.mil/dtic/tr/fulltext/u2/a181244.pdf...

Hi all I was hoping someone could shed some light on the following:- I am trying to understand what Yield strength is and understand the exact limit of where elastic and plastic deformation occurs on a stress strain curve. Correct me if I am wrong but I define:- Yield strength as the amount...

Homework Statement Show that if you add a total derivative to the Lagrangian density ##L \to L + \partial_\mu X^\mu##, the energy momentum tensor changes as ##T^{\mu\nu} \to T^{\mu\nu}+\partial_\alpha B^{\alpha\mu\nu}## with ##B^{\alpha\mu\nu}=-B^{\mu\alpha\nu}##. Homework EquationsThe Attempt...

<< Mentor Note -- OP has been reminded to use the Homework Help Template when posting schoolwork questions >> my think if ## \hat{r} = \sin(θ) \cos( φ) \hat{x} +\sin(θ) \sin( φ) \hat{y} +\cos(θ) \hat{z} ## ## da = R^2 \sin(θ) dθdφ \hat{r} = da_{x} \hat{x} + da_{x} \hat{y} + da_{z} \hat{z}##...

Ok, so I would like to know if something is possible. I have a bamboo ring, which has been cut in half, and had a piece of fabric soaked in epoxy placed in between to act as a flange. Under compression, the main failure occurs at the fabric/bamboo connection, as a result of shear stress. Is...

Homework Statement 1.Explain how one with the help of the free body diagram can calculate forces and moments on the vertical cut line through the beam in a distance 1 m to the right from the point C. 2. Explain how one calculate size and distribution normal stress of the cut line. The beam...

Homework Statement Homework Equations maximum torsional shear stress = (Torque*radius)/polar moment of inertia The Attempt at a Solution I am lost on equation(4-14), I looked through the textbook but didn't find a derivation.

Hello, I am in an engineering summer camp, but since this is a condensed course and it seems the professors assumed the class already had some background in the subject, I am slowly getting lost. They gave us practice tests from previous years, and I was wondering if someone could show me how to...

Homework Statement I am following a textbook "Seismic Wave Propagation in Stratified Media" by Kennet, I was greeted by the fact that he decided to use cylindrical coordinates to compute the Stress and Strain tensor, so given these two relations, that I believed to be constitutive given an...

I am trying to evaluate SIF for 3D plate using ansys APDL. Please share tutorial/notes if available.

My question is simple. Why do we need 9 different quantities, ie 1 normal stress and 2 shear stresses on 3 different planes, to define stress at a point? example: http://www.geosci.usyd.edu.au/users/prey/Teaching/Geol-3101/Strain/stress.html I think it should be enough to define the 3 stresses...

Hello there, I am having a problem to solve in exams. I think it's because am freezing but that's just a speculation. I am a physics-math junior and I study really well, solve without looking at solutions and focus and understand the material. Yet whenever I enter an exam I can always solve the...

Bathe (reference below) outlines the updated Lagrangian (UL) and total Lagrangian (TL) approaches using the second Piola Kirchhoff (PK2) stress. Others (i.e., Ji, et al. and Abaqus) define the UL and TL formulations in terms of the Kirchhoff or the Cauchy stress in rate form. This form requires...

My partner and I are arguing over what types of stresses are present on a point of our project. We must calculate the stress by hand using Von Mises eq uations. The picture shows a diagram of what's going on. We are calculating the stress on the mounting plate from the quarter of the motors...

My mechanics of materials book states that in order for an element to be in equilibrium it must have equal horizontal and vertical shear stresses. However, it also states "The shear stresses in the web of a wide-flange beam act only in the vertical direction and are larger than the stresses in...

Hello everyone, I've been messing around with FEA and I'm trying to match my simulation with hand calculations. While doing this it occurred to me that i really don't understand why we use avg shear stress instead of maximum shear stress when determining the safety factor of a structural member...

Homework Statement Homework Equations δ=PL/AE σ=Eε The Attempt at a Solution a: (2L-x)/x b: For AC, force acting on it = 2P*x/(2L-x) ##linearly proportional δ=(2P*x/(2L-x))*(2L-x)/[(πD^2/4)*E]=(8P*x)/[(πD^2)*E] am i wrong in part b? thanks

Homework Statement Homework Equations direction of normal and shear stress The Attempt at a Solution I view it like A and C are the same; B and D are the same... as both shear stress of A and C points outwards and shear stress point to the corner with 135 deg vice versa for B and D what...

A friend shared this article with me recently and I thought I might post it here for discussion. The Human Cost of the Pressures of Postdoctoral Research While I'm not sure that academic journals are the right venue for such statements, I agree that as a community it's important for us to have...

Homework Statement Mohrs circle question - https://imgur.com/SKeTUXN Shear stress in I beam question - https://imgur.com/34yTyCAHomework Equations Mohrs Circle - None Shear stress in I beam - I = d . b^3 / 12 tmax = (F / I . b) . (A1 . y1) + (A2 . y2)The Attempt at a Solution For the...

Homework Statement See attached photo Homework Equations Stress = F/A Area = pi d^3 / 4 Sum F h = 0, Sum F v = 0, Sum M = 0 The Attempt at a Solution Hey everyone, after reading the question a number of times and not knowing for certain where to start, I figured because the stress and area...

Homework Statement find bending stress in x and y dir Homework Equations I = bh^3/12 + ad^2 Stress = Mc/I The Attempt at a Solution I = bh^3/12 + ad^2 Stress = Mc/I see attached calculations My prof gave us a question where we have a motor (20" tall) sitting on a frame with a load of...

Just wish to know if there are GOOD EXAMPLES out there on the topics above. I am particularly looking for thermal creep using ANSYS Mechanical Workbench ... Thank you much.

<<moved from a technical forum, no template>> Need a Solution ASAP!

Hi, when working with NS equations the stress tensor can be written as ##\nabla \tau = - \nabla P + \nabla \tau_{v}##, where ##\tau_{v} ## is \begin{pmatrix} \tau_{xx} & \tau_{xy} & \tau_{xz} \\ \tau_{xy} & \tau_{yy} & \tau_{yz} \\ \tau_{zx} & \tau_{zy} & \tau_{zz} \end{pmatrix} This...

I have few natural coping skills to deal with stress. Lately, my stress is so bad that my normal routes aren't working. I'm trying not to have sex but only once or twice a week. I can't even focus to do anything I used to find enjoyable and relaxing. I'm trying to drink a few days a week, but it...

Hi, I had been reading about the fatigue stress concentration factor (Kf) which is reduced compared to the geometric stress concentration factor (Kt). The reduction in turn dpends upon the material's sensitivity to notches...

In humans, as well as in animals, aggression occurs more often in men. Frustration produces a readiness for aggression. When the source of the frustration cannot be challenged, the aggression gets displaced onto an innocent target with violent behaviour. Displacement behaviour is associated with...

Hi, I suffer from bad anxiety and depression along with ADD-PI. I know I sound like a basket case; but, have the greatest amount of enthusiasm for furthering my education. I'm in my late twenties and have dropped out of college due to the above issues. However, the curiosity is still unrelenting...

Good day all, I have an issue regarding the theoretical concept regarding the stress generated by the skew bending in a rectangular cross section for example the formula used to calculated the stress is while when it is a circular cross section we have the following formula I really...

Hi folks, I'm currently working on a final year project on the design of a plunger pump. The most recent area I have been studying is the loading on different joints in the pump. For a simplified example I have determined the maximum torque load on the crankshaft from the plungers for the...

Hi, below i have attached a exercise sheet question with the solution, however i don't quite understand it. In torsion, the maximum shear stress of a shaft is determined using the max radius of the shaft. Also, when comparing two sections, the one with the larger radius gives a higher shear...

Hello, When choosing a polynomial stress function Φ to satisfy the biharmonic equation, how does once decide on which order of the polynomial to choose? For example, is it based upon the number of boundary conditions, like a 3rd order polynomial would satisfy 3 boundary conditions?

Say I wanted to set up EFE for the Earth and moon. How do I actually go about filling the stress energy tensor? I'm referencing the wikipedia page. So the time-time should be approximately E/c^2V, so for the Earth moon system ##T_{00} = \frac{3}{4\pi r_E^3}\frac{1}{c^2}(M_Ec^2 + 2/5...

Homework Statement A rectangular Cross-section beam, 20cm deep by 10cm wide, is subjected to a maximum bending moment of 360kNm A) Calculate the second moment of area of the beam cross-section B) what is the maximum stress in the beam under this load C) if the value of E for the beam of...

Homework Statement I am given c11, c12, and c44. What is poissons ratio ν and the E modulus E [100] for a single crystal for uniaxial strain in [100] (if Fe is isotropic)? ii) What is the anisotropy factor A? (iii) There is: sigma=[100 0 0; 0 100 0; 0 0 0]Mpa What is the transverse strain in...

A plate is riveted with a rivet having small rod like projection over the head and the point as shown in drawing.Considering we fix the plate to a vise,and then giving torque to the Rivet Rod;What will be the Maximum Torque the rivet can withstand without getting loosened and how to calculate...