Stress Definition and 1000 Threads

I have been given a question to recap by my tutor as i find this topic fairly difficult. A steel column is 90cm long and 150mm diameter. If a hole 100mm diameter and 60cm long is bored out, calculate the total compression of the column when carrying a load of 1MN. Take the modulus of...

In Rc Stephen's book Strength op materials, the longitudinal stress in a cylinder(see) attachment caputure.jpeg. My question is how is the area(pi X d X t ) is derived as my calculations show that this area should equate to (pi x d x t + t x t)

Hey guys I'm having trouble understanding the full nature of the energy momentum tensor. I understand the whole "matter flow and energy flow" affects the curvature of the space time metric being used. What I don't understand is the role of stress and shear - stress. Is the stress being described...

Hello, I am trying to understand the Maxwell Stress Tensor. Specifically, I would like to know if it is coordinate-system dependent (and if so, what the expressions are for the stress tensor in cylindrical and spherical coordinates). Griffiths gives the definition of the maxwell stress tensor...

Hi, I have a question which was raised after reading the article "Derivation of the string equation of motion in general relativity" by Gürses and Gürsey. The geodesic equation for point particles can apparently be obtained as follows. First one takes the stress tensor of a point particle...

Homework Statement A cantilever beam (length, L, height, 2h, thickness 1). The top surface is subjected to shear stress tsubxy = s. Determine the stress function psi. The boundary conditions at the end of the free end (x=L) can be satisfied by integration (e.g., traction free can be...

Homework Statement (Note: I assumed SI units. So lb=N, inches=m) http://img535.imageshack.us/img535/4355/10594047.jpg The attempt at a solution For part (a) and (b) I have: [PLAIN][PLAIN]http://img219.imageshack.us/img219/3049/83432480.jpg However, how do I go about doing...

Homework Statement [PLAIN]http://img12.imageshack.us/img12/6109/17007711.jpg The attempt at a solution For part (a), I can only find a normal compressive stress. It is as follows: \sigma_{c} = \frac{F}{A} \sigma_{c} = \frac{100*9.81}{\pi(0.013)^{2}} \sigma_{c} = 1847704 Pa...

Hi,can u please tell me the difference between the Stress tensor & the Stress matrix...

I've been working my way through GR using mainly D'Inverno's Introducing Einstein's General Relativity, but with MTW as well and a couple of other books. I began to get a sense of what was going to happen and got a big surprise when I reached the Schwartzschild solution. The process goes...

I'm taking a continuum mechanics course and we use the 3*3 stress tensor a lot. The problem is that I do not understand what each component mean. What does the tension(Pn normal(Pnn and tangent(Pnt tension mean, or just Pxy?

Homework Statement Given: hollow steel shaft Torque = 5400 Nm Torsional Shear = 150 MPa Required: Inside diameter Outside Diameter Stress on the inside of the shaft Homework Equations The Attempt at a Solution I solved both the diameters which are 64.49 mm and 48.37 mm...

Homework Statement Find the maximum shear stress for \sigma _{xx} = 120 MN/m^2, \sigma _{yy} = 50 MN/m^2, \tau _{xy} = 40 MN/m^2Homework Equations \sigma _{min} = 0.5(\sigma _{xx}+\sigma _{yy})-0.5((\sigma _{xx}-\sigma _{yy})^2+4\tau _{xy} ^2 )^{0.5} = 31.8 \sigma _{max} = 0.5(\sigma...

bending stress in beam, help me ! Homework Statement Homework Equations singularity function bending stress (max) = { (M max)/I } * ( a/2) The Attempt at a Solution after writing the singularity function, and compute reactions force I found that the maximum bending moment should be 12.04...

A steel wire of length 1.92 m with circular cross section must stretch no more than 0.210 cm when a tensile (stretching) force of 390 N is applied to each end of the wire. What minimum diameter is required for the wire? Express your answer in millimeters. Take Young's modulus for steel to be Y...

Hi all - first post at PF. As a 'science enthusiast' with no training in the tensor math of GR, was initially bewildered by the common assertion that still hypothetical 'dark energy' would act as a source of 'negative gravity' despite having positive energy density. Finally grasped that pressure...

When the term uniaxial comes I imagine something being pulled or pushed in one direction only. Confusion is that I read online http://enpub.fulton.asu.edu/imtl/HTML/Manuals/MC105_Cantilever_Flexure.htm" that a cantilever beam loaded at the end is also in uniaxial stress. This is what I can not...

In a 3-D stress problem when we draw the 1st & 2nd & 3rd mohr circle for each plane what is a case or situation in which the 3rd mohr circle is smaller than the 1st & 2nd ones?

Homework Statement A simple pin-connected truss is loaded and supported as shown in the figure. All members of the truss are aluminum pipes that have an outside diameter of 4 in and a wall thickness of .226. Determine the normal stress in each truss member. Homework Equations Normal...

What happens to a body's stress if the temperature goes up or down?What are the equations?

Was a bit fuzzy as to whether this better fit HW or here, but since there really is no question associated with it, figured this made a bit more sense. I have a couple basic questions about the stress tensor: T_{ij} = \epsilon_0 \left( E_i E_j - \frac{1}{2} \delta_{ij} E^2 \right) +...

So I'm working on yet another problem, and have come to a minor stump. 2 wires run parallel with the Z axis in the xz plane, one with current I-1, other with current I-2. I need to determine the components of Maxwell's stress tensor at a field point P, where P is a point on the yz plane (x=0)...

Homework Statement Select a suitable steel rope to suspend a lift from a winch. The weight of the lift is variable as is the weight and diameter of the ropes the lift is suspended from. As an example, I'll use 13mm for the ropes diameter and 0.63kg/m for the rope mass, the total length of the...

\hat{N}=\{\vec{E},\vec{D}\}+\{\vec{H},\vec{B}\}-\frac{1}{2}(\vec{D}\cdot\vec{E}+\vec{B}\cdot\vec{H})\hat{1} \hat{1} - unit tensor If I look \{\vec{E},\vec{D}\}. I know that \{\vec{E},\vec{D}\}=\{\vec{D},\vec{E}\}^* But when I can say that \{\vec{E},\vec{D}\}=\{\vec{D},\vec{E}\}? and when...

hi, I wonder if the stress energy tensor formulation of general relativity has been well experimentally verified, since the schwarzchild metric is used most of the time. for example, is there any experimental evidence that an increase of the pressure with the same energy density, increases...

1. Problem Statement The long bolt passes through the 30-mm-thick plate. If the force in the bolt shank is 8kN, determine the average normal stress in the shank, the average shear stress along the cylindrical area of the plate defined by the section lines a-a, and the average shear stress in the...

Something has been bugging me for a long time, since I took my first statics class a few years ago. I have a problem with a common figure found in many statics books. I have attached the figure to my post. My question deals with the delta V added to the shear force on the right side of the...

Homework Statement well guys i am in 10 th standard...jus out of nowhere i challenged a person that i can find out the maximum weight a trpod can take...now i have no clue how to solve this problem pleasez help me out its 3.5 m hollow shaft with 2 inch outer dia and 5 mm thickness and...

When extracting a Principal stress for the component, how to differentiate/seperate/identify the tensile and compressive stress in it?

Shear stresses in shrink fit assembly? I'm trying to figure out what shear stresses there would be from a shrink fit assembly, if any. You have a cylindrical solid shaft and a cylindrical hub, where the shaft diameter is greater than the hub's hole diameter. The shaft cooled and thus shrunk and...

Hi, I need to find the stress taken up by the fibres in the longitudinal direction, when a load of 25kN is applied to a continuous aligned composite with the diameter of 2cm. 60% matirx with E=2.8Gpa and 40% glass fibre E=73Gpa. Attempt at solution Known values V_m = 0.6, E_m =...

Principle stress states question, anyone help?? Homework Statement Neutron diffraction is used to measure the residual strains near to a weld in an aluminium plate. The aluminium has a young’s modulus E of 70GPa and a poisons ratio of 0.3. The three principal strains obtained are ε1= 2400 με...

I have calculated the contact stress for a sphere in a socket using formulas provided in Roark's formulas. But my problem is that the sphere is actually in contact with two sockets - upper and lower sides, so there are actually two contact areas. Can I just multiply the contact stress I...

Homework Statement Your given two designs for the same component. Design 1 has a stress pf 120 Mpa design 2 has a stress of 90Mpa. They are both made from the same material and the ultimate strength is 290Mpa and the yeild strength is 250 for both. The question is if yeild strength is the...

1. \tau = (V*Q)/(I*t) Q=first moment of area, t=width, I= Ixx and V=shear force 3. First I found the greatest shear for to be 10Kn at point b Then I found second moment of inertia = 1360000 Now I need to calculate for Q (first moment of area) = A*y...

Question: A bar has a unknown tensil load. A gauge shows that the strain is 400x10^-5. Work out the Stress & Tensile Load (there should be an image attached of the beam. Also the Youngs modulus is given as 180GNm^-2, but I believe this is for a later part of the question) Relevant...

Homework Statement For a plane stress condition (stress z-axis = 0 ), prove the following relations if strain x-axis and strain y-axis are determined by experiments. σ_x=(∈_x+v∈_y/1-v^2)E & σ_y=(∈_y+v∈_x/1-v^2)E where: σ_x = stress in x-axis σ_y = stress in y-axis ∈_x = strain...

hi, I would like to know if the contribution of some electromagnetic field through the electromagnetic stress energy tensor can decrease the intensity of gravity. it has negative components. can it decrease pressure? in such case, this would lead to some kind of relative antigravity...

Just a quick question: I was wondering whether the Force Applied to a spring equates to the stress and whether the Displacement of a spring equates to the strain. I have been researching this on the internet and the units of stress are completely different to Force Applied and the same for...

Hello, so here is my problem. Homework Statement I am given tensile data, which is displacement (mm) and load (kgf). also I am given width(mm), thickness(mm), gauge length (mm) and cross-head speed (mm/min). How do i make a stress strain curve from this? The Attempt at a Solution...

Homework Statement stress tensor in cartesian components. \sigma is the stress tensor. e_i are the basis vectors Homework Equations \sigma \cdot \sigma The Attempt at a Solution I tried to write out the components with a cartesian basis: \sigma=\sigma_{ij} (e_i \otimes e_j) But then I'm...

1. I didnt understand why some people extracting Principal stress for aluminum material which is subjected to dynamic loads(acceleration).Why not Von Mises? 2. Which has more advantages in predicting Fatigue Life and how? 3. How will you distinguish between tensile and compressive...

Homework Statement We've been given several questions and told to use the internet to find out the formulas for them. But I can not find the right ones anywhere! If anyone could just give the formulas that's all I need! A seat is attached by a simple pin of a circular cross section...

I'm looking to buy a book or three on pipe stress analysis and design. If you work in this field, please make some recommendations for me. Thanks,

Hello I am trying to understand if is it reasonable to use "slip walls" or "zero shear stress" to model smooth walls. I am working with turbulent air flows in ducts. Please share your comments.

if there is a torque on a channel section twisting it axially what stresses do u expect to be on the side face ??

Homework Statement A steel beam is used in the road bed of a bridge. The beam is mounted between two concrete supports when the temperature is 23⁰C, with no room for thermal expansion. What compressional stress must the concrete supports apply to each end of the beam, if they are to keep the...

Homework Statement The magnesium allow tube (AM1004-T61) AB is capped with a rigid plate. The gap between E and end C of 6061-T6 alluminum alloy solid circular rod CD is d[m] when the temperature is T_1 degrees celcius. [PLAIN]http://img27.imageshack.us/img27/8867/problemwn.jpg The...

Hello, I need help with a simple stress analysis. I have a 25 in x 25 in sheet of Lexan that's 0.125 in thick and is constrained from all sides (the Lexan is used a protective shield). I want to know if a small water jet from a pressure vessel at 7000 psi would crack./break that sheet of...

Homework Statement A steel strip of breadth 50 mm and depth 3 mm needs to be bent around a drum of diameter 4 m. What bending moment is required and what will be the maximum stress produced? The modulus of elasticity of the steel is 210 GPa Homework Equations \frac{M}{I}...