What is Tensile stress: Definition and 33 Discussions
In continuum mechanics, stress is a physical quantity that expresses the internal forces that neighbouring particles of a continuous material exert on each other, while strain is the measure of the deformation of the material. For example, when a solid vertical bar is supporting an overhead weight, each particle in the bar pushes on the particles immediately below it. When a liquid is in a closed container under pressure, each particle gets pushed against by all the surrounding particles. The container walls and the pressure-inducing surface (such as a piston) push against them in (Newtonian) reaction. These macroscopic forces are actually the net result of a very large number of intermolecular forces and collisions between the particles in those molecules. Stress is frequently represented by a lowercase Greek letter sigma (σ).
Strain inside a material may arise by various mechanisms, such as stress as applied by external forces to the bulk material (like gravity) or to its surface (like contact forces, external pressure, or friction). Any strain (deformation) of a solid material generates an internal elastic stress, analogous to the reaction force of a spring, that tends to restore the material to its original non-deformed state. In liquids and gases, only deformations that change the volume generate persistent elastic stress. However, if the deformation changes gradually with time, even in fluids there will usually be some viscous stress, opposing that change. Elastic and viscous stresses are usually combined under the name mechanical stress.
Significant stress may exist even when deformation is negligible or non-existent (a common assumption when modeling the flow of water). Stress may exist in the absence of external forces; such built-in stress is important, for example, in prestressed concrete and tempered glass. Stress may also be imposed on a material without the application of net forces, for example by changes in temperature or chemical composition, or by external electromagnetic fields (as in piezoelectric and magnetostrictive materials).
The relation between mechanical stress, deformation, and the rate of change of deformation can be quite complicated, although a linear approximation may be adequate in practice if the quantities are sufficiently small. Stress that exceeds certain strength limits of the material will result in permanent deformation (such as plastic flow, fracture, cavitation) or even change its crystal structure and chemical composition.
In some branches of engineering, the term stress is occasionally used in a looser sense as a synonym of "internal force". For example, in the analysis of trusses, it may refer to the total traction or compression force acting on a beam, rather than the force divided by the area of its cross-section.
Trying to calculate the maximum stress that would occur in the attached assembly...
The assembly consists of a tube sandwiched between two plates that are bolted down to a larger plate with an M6 bolt. Each of the two plates have a 400N force acting on them which is perpendicular to the axis of...
I'm wonder how one could calculate the total mega pascals total mega pascals that can be applied to a spinning flywheel before it exceeds its tensile strength
example: a cast iron flywheel is spinning at 10,000rpm(Tangential velocity = 104.72) it has a radius of 100mm and a weight of 500g...
So I've been looking at a few material tests and they all start with a rectangular sample of the material, loaded into a machine which extends them by increasing load at a constant rate and measures the strain/stress till the point of material fracture. The yield stress is measured in usually...
1.A rectangular steelbar of length subjected to tensile force of 80kN. Calculate the change in length if the width and thickness are (40 & 25)mm respectively. (E = 207 GN/m2).
Homework Equations
E= stress/strain
stress = F/A; F =80kN
strain = dL/L
3. I just want to know what to use for the...
Homework Statement
Two lengths of steel plate 100mm wide and 15mm thick are riveted together by a single 18mm diameter rivet. If the joint carries a tensile load of 8kN calculate:
a) The shear stress in the rivet
b) The tensile stress in the perforated plate
Homework Equations
stress = force...
Isn't the force calculated twice here? For example, the force along AB is at first calculated for the resultant force along OB, then for the resultant force along AC.
I think the compression and tensile stress should be ##\frac{F}{2a}##.
Homework Statement
can someone explain about part b (tensile stress) here? in which way does the stress act?
Homework EquationsThe Attempt at a Solution
FromW wikipedia, tensile stress refres to the stress to break a rope...How does it related to the case above?
Hi,
I'm struggling with finding the tensile stress at the mid-span of this beam. I've done the previous questions but have no idea how to begin with this one as I've never dealt with this question before.
What is the general method?
Correct answer is 1.66MPa.
Thanks.
The cross-section of a cost-iron beam is shown in figure below, the loading being in the plane of the web, the upper portion of the section being in compression. If the maximum permissible stresses are 2000 kg/ cm2 in tension and 3000 kg/ cm2 in compression, find the moment of resistance of the...
Determine the tensile stress in the bolted connection shown below for the load F = 210 kN. Using a safety factor of 2, determine whether the plates will fail or not if the yield strength of the plate material is 270 MPa and the thickness of the plate is 12 mm. The nominal diameter of the bolts...
Suppose, a mild steel bar is being pulled from both ends.The stress acting on it will be tensile in nature.There is no compressive stress on material in this situation.When the pull exceeds material's yield strength,plastic deformation and strain hardening will occur.If pulling force is...
I'm studying elasticity right now in my chemistry class, and I'm confused as to what exactly tensile stress (and maybe compression stress too ) might mean. It's given in N/m^2. And you're stretching the material.
Is the cypher I'm given indicative of what's happening only one side? Indicative...
I was solving this paper, but got stuck on this question, and it's been bugging me endlessly. I don't know what I'm missing. Here's the question:
A rod of 20 dia is fixed to the ceiling of a roof on one end. A rotor of 50 kg mass is attached to the free end with bearings. The CG of the rotor...
Homework Statement
A cable containing 37 strands of 0.0250" diameter steel wire successfully supports 1000 lb load in tension. Calculate tensile stress? Do you think this is a reasonable and safe design stress level?Homework Equations
tensile stress = F/A
The Attempt at a Solution
A = [...
http://www.glassalchemy.com/media/upload/image/stressfig1.gif
In the manufacturing of glass(flat glass),the outside cools first followed by the inside.So,this means that the outer surfaces compresses on the hot inner surface.What I don't understand is how the tensile stresses are developed on...
Homework Statement
An Aluminum cable of length 3.5m has 15,000 N tensile force acting on it if the wire is only allowed to be stretched by 1mm before it breaks,
What must be the radius of the wire if the Young's modulus of Al is 6.9 x 10^10 N/m^2?
I am also supposed to find the tensile...
(a) The steel cable to the hoist is 15m in length and has a diameter of 25mm. Its steel has a maximum permissible working stress of 200N/mm2 and a Young’s modulus of elasticity of 210,000N/mm2. The maximum load allowed on the hoist is 75kN. Determine the following:-
(i) the cross-sectional...
Homework Statement
L=52 in
A=2.76 in^2
E=10.4*10^6 psi
Homework Equations
σ=F/A
ε=σ/E
δ=εLThe Attempt at a Solution
4) σAB = (3P)/A
ε=(3P)/(AE)
δAB=(3PL)/(6AE) → δAB=(PL)/(2AE)
solving for P
P=[0.17*2*2.76*(10.4*106)]/52 → P=187680 lb → P=187.7 kip
5) Because AB and CD are in tension i...
Tensile stress given theta and force (I'm kinda desperate)
Homework Statement
Aluminum wire is lightweight. You can hang a piece of it nearly horizontally with very little tension. After having done so, you then hang a HEAVY (25 kg) block from the wire. The wire sags to make an angle of 12...
I need to find the stress σ (defined as normal force/area, in N/m^2) for the following simple situation. The forces are not equal. I can't wrap my head around what's going on - the whole system should be accelerated, so what's the final force that should be used for calculating the stress?
Hey guys!
I'm really stuck and would be grateful for any help. I'm a postgraduate researcher, though not a physicist so this may be a relatively simple problem for some of you (I hope!).
I use a program called Bluehill which is coupled with an Instron machine. The instron is a mechanical...
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...
Hi
I am trying to solve this problem. I will present my solution though I couldn't get the tension right.
At 40 Celsius , there is no tension in the wire. When the wires are cooled , they contract and the tension increases. But the tensile stress, which is force per unit area, will remain...
Homework Statement
Calculate the tensile stress in a rod 40 mm in diameter with a load 200 KN ?
Homework Equations
pi*r^2
The Attempt at a Solution
3.14 * (20*20) = 1256 mm^2
200 * 1000 = 200 000 N
200 000 / 1256 = 159.24 N/mm^2
Tensile stress = 159.24 N/mm^2...
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...
A strain gauge has a unstrained resistance of 120 ohms, gauge factor of 2.0 is connected to steel girder so it experieces tensile stress. If strained resistance of gauge is 120.13 ohm. How do i calculate the tensile stress value?
I have looked all over the internet for equations relating but...
A strain gauge has a unstrained resistance of 120 ohms, gauge factor of 2.0 is connected to steel girder so it experieces tensile stress. If strained resistance of gauge is 120.13 ohm. How do i calculate the tensile stress value?
Homework Statement
How would you define the ultimate tensile stress of rubber?
Homework Equations
If I had a force/extension graph of rubber, what point in the graph would show me the value of the ultimate tensile stress??
The Attempt at a Solution
Is it the same thing as ultimate...
I'm having a problem finding and equation that will give me the tensile stress acting on a spinning ring, like the rim of a flywheel, that is trying to "pull itself apart". The ring has no spokes or disc, but is just a ring spinning on its axis. I need to know how fast the ring can spin...
Homework Statement
A load of 172 kg is supported by a wire of length 2.07m and cross-sectional area .143cm^2. The wire is stretched by 0.149 cm. Find tensile stress, strain, and Young's modulus.
Homework Equations
stress= F/A
strain= ∆L/L
E= stress/strain
The Attempt at a...
Homework Statement
"The axial load for a given test sample carries 1590 N. Calculate tensile stress at sections (1) and (2) assuming the sample thickness is 5mm. (Rectangular cross section).
http://img208.imageshack.us/img208/121/tensilestressby1.th.jpg
Homework Equations
normal...