1. ### Stress in a pipe wall

Consider a pipe. The pipe is not crushed by the air pressure because the same air pressure is acting from inside the pipe. But this means that the material of the pipe is being compressed on both sides by some air pressure. So is it correct to say that the through-thickness stress in the pipe...
2. ### I Stresses Caused By Deformation For Bending

Hi. Say you apply a moment on a beam and bend it into an arch. If you take a free body diagram of a section of the beam you would need normal stresses in the radial direction to balance the forces: I have never seen this brought up before though -- is it correct logic? Also, is this sort of...
3. ### Some questions about Friction in fluid flow

I have few conceptual doubts in fluid mechanics. Here is the one I will ask first. I want to understand the force direction acting on the solid liq interface during fluid flow, Lets say a fluid is flowing in a pipe. Now the fluid applies a shear stress at the walls of pipe in the direction of...
4. ### Calculate the maximum vertical point force P that this beam can sustain

A simply-supported steel beam with a vertical point force P is shown in Fig. 2(a). A cross-section of the beam, which is composed of two identical C-shaped members bolted back-to-back, is shown in Fig. 2(b). Both C-shaped members have a uniform thickness of 1 cm. Pairs of bolts are located at a...
5. ### Lines of Stress in a Material

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...
6. ### Beams-Bending stress exercise

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...
7. ### I Normal Stress

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
8. ### How to decide which component is best in terms of stress and deformation?

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...
9. ### Fluids doubt

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...
10. ### Find the stretch of a steel wire in a static equilibrium problem.

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...
11. ### Help with formulas for calculating pressure

Hi! This is my first post on here. I need to purchase an air cylinder, most likely hydraulic. The cylinder will have a forming die attached on the end and will be used to crimp two small stainless steel tubes together. The crimp will occur at an offset of .004 inches from each end of the tubes...
12. ### Shear stress direction and the velocity gradient

1)In a flowing fluid in laminar fashion we know that it flows in planes which slides over each other, Lets 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...
13. ### I Angular speed that breaks a spinning body apart with inertial stress

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) ...
14. ### Thermal Expansion of a Wire Connected To a Rod

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...
15. ### Poisson's Ratio

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...
16. ### Stress and Strain tensors in cylindrical coordinates

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...
17. ### Testing How to stop freezing in exams

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...
18. ### Finding a maximum force in a beam type system before failure

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...
19. ### Shearing when bolts are arranged radially

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...
20. ### Automotive How to Calculate maximum torque a riveted joint can stand

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...
21. ### Other Restoring curiosity

I began to study mathematics in college because I was fascinated by the subject and have a naturally high degree of curiosity for it along with the rest of the sciences--but stress, depression and other factors take away that curiosity as I progress through each semester, leaving me bored...
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### Vertical stress in soil

Homework Statement In this question , i suspect the total vertical stress at the center of the clay is incorrect . Homework Equations The Attempt at a Solution In the figure , we can see that the water table is art 2m below the sand . So , the 2m sand thick should be dry , am i right ? Only...
23. ### I Continuum mechanical analogous of Maxwell stress tensor

Maxwell stress tensor ##\bar{\bar{\mathbf{T}}}## in the static case can be used to determine the total force ##\mathbf{f}## acting on a system of charges contanined in the volume bounded by ##S##  \int_{S} \bar{\bar{\mathbf{T}}} \cdot \mathbf n \,\,d S=\mathbf{f}= \frac{d}{dt} \mathbf...
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### Uniaxial press: 1 ram vs 2 rams

Assume to have 2 hydraulic presses for compacting powders with the following designs: Press A has 2 rams that apply force in opposite directions, pointing towards the powders in the middle Press B has 1 ram that applies force in one direction, towards the base of the press My colleagues keep...
25. ### I Stress exerted on a wooden cube dropped on concrete floor

I wonder if it is possible to at least estimate the stress (or the impact force) that the cube in question will experience due to the collision with the concrete floor. Assumptions: 1. The cube is dropped from height h 2. The cube is relatively small, thus we can neglect air resistance...
26. ### By how much is each post compressed?

Homework Statement A large 30000 L aquarium is supported by four wood posts at the corners. Each post has a square 6.00 cm x 6.00 cm cross section and is 90.0 cm tall. Take Y=10^10 for wood Homework Equations ΔL = FL/AY F = ma ρ = m/V The Attempt at a Solution So the total area is 0.06 * 0.06...
27. ### Determine the highest tension stress and the highest compression stress

Homework Statement Determine the highest tension stress and the highest compression stress along the top edge of the intel. Homework Equations stressx = Mx*y / Ix Ztop = Ix / ytop stress (max top) = Mx - Ztop The Attempt at a Solution