Stress Definition and 1000 Threads

Homework Statement A fair ground ride comprises of a car, connected to an arm, secured to the main driver by a pin. It rotates about a vertical axis. when operational: a) what type of stress is experienced by the pin?, and what type of stress is experienced by the arm? b) if the max allowable...

Homework Statement So we have a compound cylinder, 100 mm internal diameter, 200 mm common diameter and an outer diameter of 300 mm. The pressure created by shrinking the outer cylinder on the inner cylinder is 30 MPa. If the maximum hoop stress on the outer cylinder is 110 MPa, what is the...

Hello, I am the parent of a ChemE student. He is a Jr at a California State University. He has some learning difficulties which makes problem solving / life issues a bit tough on him. I am just trying to help him out. He failed Statics last fall. He just came home from Spring Break and...

Hi everyone, I've taken a course at uni that may be a little bit over my head, and am pushing through an assignment for it at the moment in an attempt to do well. I've hit a bit of a roadblock on one question though, so am hoping that someone kind here can help me out! The question is...

Why can there sometimes be a difference observed between them?

Homework Statement a thin wire of crosssection area 10^-2 m^2 is used to make a ring of radius 1/10 m. it is given ω=2 rad/s on a smooth table about its centre. find stress in ring?( mass/length of wire is 1 kg/m.) Homework Equations s=f/a f=mv^2/r The Attempt at a Solution my...

In GR normal stresses as per the three lower diagonal terms T11, T22, T33 in the SET (stress-energy tensor) (e.g. http://en.wikipedia.org/wiki/Stress%E2%80%93energy_tensor) are source terms for gravitating mass. And afaik true for any similar theories of gravity. Owing to their being resolved...

curious as to the proper way to model this. beam is symmetric so centroid is in the middle (used to calculate distance from centroid d in bending moment of inertia equation) bending moment of inertia is I =\sum(I + Ad2) I=\frac{1}{12}bh b=base h=height d=distance of the area's...

For fluid with viscosity \mu our stress strain relationship takes the form \sigma_{ij} = -p \delta_{ij} + 2 \mu u_{ij}. I was wondering how to express this in cylindrical coordinates. The strain tensor I can calculate in cylindrical coordinates (what I get matches eq 1.8 in [1]). But how...

Homework Statement For my physics course work i need to work out the uncertainty of stress, is there formula for this or is it just the largest value of uncertainty for example is my area is 7.548E-08 +/- 6.452% and my force 2 +/- 25% Homework Equations stress= Force/area The...

Hi All! I am currently busy working on a new knife gate valve design. I have an actuator with a mass of 200 kg attached at the top of the valve. The bottom plate of the actuator is 28 mm thick and I am going to use this plate directly to fasten the actuator(see attached drawing for plate...

First of all, thanks for all the helpful comments to my previous posts. I'm trying to get a grasp of stress tensors and have been doing some studying. In the literature I've been looking at, it says something about the eigenvalues of stress tensors and the principle stresses. This is...

Homework Statement An alloy steel shaft has an outside diameter of 100 mm. A central hole of 60 mm diameter is bored in part of its length as shown. Compute the shearing stress in the hollow section if the stress in the solid section is 200 MPa. Homework Equations angle = TL/GJ t = torque L...

Homework Statement I need to find the bending moment of a washer shape for a project I'm working on so I don't have an exact problem statement. Imagine that a washer was fixed (not pinned) around its inner radius and a force were applied evenly around the outer radius. How can I go about...

I am trying to calculate the stress applied to a 1' x 2' piece of vinyl. The vinyl is welded to the bottom of an above ground pool and is used to hold the leg support, which holds up the side of the pool, in place. There is a leg support every 4'. A picture of the pool can be found at...

Hi can anyone help how to calculate torsional shear stress for square bars Regards, venkata prasad.G

hello sir, I have completed my b.tech in mechanical engineering, and am looking forward to start my career in pipe stress analysis and piping design. I would be happy to receive your valuable suggestions regarding the industry, job opportunities in and abroad. thankyou, jaswanth

I have calculated a static contact stress of 670 N/mm2 using formula from Mechanical Engineering Design, Shigley, 5th Edition. My problems lies that there is no acceptance criteria. I'm using Grade 5 Structural Steel (yield~355 N/mm2). Previous threads have stated that a 2.5 * yield can...

Hi guys I have a general query regarding Rubber O-rings. For an application , say seal between 2 mating flanges of pipes ,with water pressure say about 10bars, How exactly does the hardness of rubber effect the the sealing? Is there a direct relation between hardness & strength ? Can some...

Homework Statement I have a piece of metal with one end fastened to a table by a clamp and the other end off the table. I only know the length of the beam and the strain. I am trying to figure out the stress in order to figure out youngs module so the metal can be identified. How do I do...

Homework Statement There is a 104kg uniform log hung on two steel wires, A and B, both of radius 1.00mm. Initially, wire A was 2.70m long and 2.00mm shorter than wire B. The log is now horizontal. Note that the centre of gravity (com) is not necessarily centered between the wires and the...

Hi Atoms are closer in FCC. Does it imply high bond strength? It does imply low bond energy.

Homework Statement A timber beam will be used to support part of the ceiling of a house. It is going to be attached to the walls as a simply supported beam, Figure 6. If three forces are applied to it and considering the weight of the beam as a uniformly distributed load of...

In fluid dynamics, always when some textbook talks about stress tensor, there is a figure like this: http://www.fea-optimization.com/ETBX/hooke_help_files/stress.gif it shows how stress tensor is defined based on a small cubic volume. I kind of understand why the shear stress τxz should be...

I have tried it and the units end up being Nm^-2 (the unit of stress) however the unit for joules is Nm.

εHi, Based on that hoary schematic cube representation in 3D for stress-strain relationship. Stress tensor {σxx, σyy, σzz, σxy, σyz, σzx} and strain tensors {εxx, εyy, εzz, εxy, εyz, εzx} can be written interchangably. Let's suppose that σzz=σzx=σzy=0 then the reamining terms are written...

Homework Statement A plastic ball is inflated enough to produce tangential stresses. σX = σY = 2000Kpa The radial thickness of the material is 1.2mm brfore inflation. Find the thickness after inflation if the tensile modulus of elasticity is 3.4Gpa and the shear modulus is 1.4Gpa...

Homework Statement derive the equilibrium state of the stress at a point in a circular pressurized vessel, membrane equation, in terms of σ_a and σ_b and internal pressure b. Figure is picture of a thin walled pressurized elliptical vessel (like a sphere vessel except with horizontal...

Hi, Please forgive me if this post is in the wrong section. I'm interested in working on a project but my physics is very rusty in terms of calculating stress and in need of help. I would like to know which is better given the below aluminum 6061-T6 tubing with similar weights to withstand...

Homework Statement Suppose that stress fractures appear in railway lines according to a Poisson process at a rate of 2 per month. a)Find the probability that the 4th stress fracture on the railway line occurred 3 months after the process of checking the new railway lines. b)Suppose new...

Hello, I am trying to determine the calculation to use to determine the force at which a disk plate will fail for the following set up. The disk is slid onto a metal bung for a roll, the disk is supported from the inside diameter for around 50mm. A force is then applied on the oppsite side...

Homework Statement My problem is to calculate the Thermal stress of a Cylindric shell with inner radius a and outer radius b the inner surface is experiencing Temperature T1 and the outer surface is experiencing T2 with T1>T2 assuming that the linear thermal expansion coefficient is a, the...

How would I use a shear force diagram and a bending moment diagram to find the maximum flexural compressive stress and the maximum flexural tensile stress? I am assuming the peaks at the bending moment diagram is the maximum tensile and compressive stresses? Am I correct? Also, is it...

Illustration attached --> https://www.physicsforums.com/attachments/42037 I have a question which requires me to calculate the maximum stress in a simple supported beam. The beam is 3 m long and rectangular and has two forces acting down vertically totalling 20 kN. The breadth of the cross...

This story is right in so many ways I can't stand it. Reducing stress before an exam has been proven to help students, focus and concentrate, resulting in better grades. Using puppies to do so is a stroke of genius, IMHO. What a cute bunch... Rhody... :biggrin: o:)

Hello guys. I need help to understand the calulation of bending stress. This topic is discussed in our lecture, and the prof shows us an animation for it. However, this topic is not on the textbook and the prof refuse to give us the link for the animation. I am wondering, do any of you know...

I have a cross-section of a beam like this one http://imageshack.us/photo/my-images/810/img0129xf.jpg/ And I have to calculate the shear stress τ. I have these things allready calculated: Xc=8cm; Yc=6.9cm Moment of Inertia Ix=2946.7 cm^4 Moment of resistance Wmin=323.8 cm^3; Wmax=427.1 cm^3...

Homework Statement View image for all details Homework Equations tao = V/A The Attempt at a Solution I went ahead and solved the force at BC and the x and y components at A, but I feel as though my solutions are incorrect. At BC I have F = 825 kN (up and to the left), A_x = 714.5...

Dear Fellows, Well, i am working on a power plant and i need to analyse the Cooling Water Piping Circuit (Supply/Return piping), i.e., from Turbine Surface Condenser to Cooling Towers and from Cooling Water Pumps to Turbine Surface Condenser. The Lines are huge around 52" NPS and are buried...

Anyone know how to use the temperature gradient in a thick-walled tube to calculate the stress seen throughout the wall (radial stress gradient)? I've been scouring the internet for a good explanation but haven't found one.

Homework Statement I am using a Vishay strain indicator with it hooked up to a strain gage hooked up 1" away from the wall on the solid beam. The beam is .5" by .5", and it is solid. The beam is 16" long and I am putting weights at the end of the beam. The weights are 1, 2, 5, 10, 15, and 20...

Maybe this is the wrong topic for this forum, but i am reading the following http://arxiv.org/abs/hep-ph/9703464 Which is on CPT violation and the standard model. I do not understand how they get to equation (9), when they write down the stress energy tensor as \Theta\mu\nu=1/2 i...

For this question, I need to find the force that will be acting on a rectangular block. E = 193 x 10^3 MPa Max. Stress = 210 MPa F= 2000N The rectangular block is fixed at both ends (bolted on to another metal object) I need to find the dimensions for this block. L, length can be as...

hi my name is adil from Pakistan.what is a reason to produce shear stress in shaft,can normal stresses is produced in shaft&where is max shear stress is apply in solid shaft at end or center.

I can now although do the maths related to plane stress etc but I have struggled to grasp the logic behind this concept. It says changing the way you see the stress by rotating the view, stress changes. My question is why ? Why is this so that we see stress with one value when standing at let's...

Homework Statement A tube 40mm inside and 60mm outside dia is to be reinforced by shrinking on a tube of 80mm outside diameter. The compound tube is subjected to an internal pressure of 50MPa and the shrinkage allowance is such that the final maximum stress in each tube is the same...

Homework Statement A flange coupling is use to transmit torque of 1500 Nm between two shafts. The coupling has four 8mm dia. bolts equally spaced on a PCD of 175mm. Determine the shear stress on the bolts Homework Equations fs=\frac{F}{A} The Attempt at a Solution Back of the...

Hi, I just wanted some clarification with respect to a few equations relating stress intensity factor to semi-elliptical and quarter-elliptical cracks in solids. The equations I have according to my notes are K_{I_{(\varphi=\frac{\pi}{2})}}=1.12\frac{\sigma \sqrt{\pi a}}{\Phi} and...

So, I'm reading Wald, and in it he talks about how the divergence-free nature of the stress-energy tensor implies "a lot" of knowledge about how matter moves in a curved space time. I'm wondering, how much is "a lot"? Can we obtain the full equations of motion from this? Wald gives the example...

Please have a look at the attached image. The two blue plates (rigid) are bolted to a red plate. Now an object with 10000 J of Kinetic energy hits the red plate and the red plate is deformed by 4 mm in the direction of energy. Due to this collision, the bolts encounter a shear stress. Can...