What is Young modulus: Definition and 34 Discussions
Young's modulus
E
{\displaystyle E}
, the Young modulus, or the modulus of elasticity in tension, is a mechanical property that measures the tensile stiffness of a solid material. It quantifies the relationship between tensile stress
σ
{\displaystyle \sigma }
(force per unit area) and axial strain
ε
{\displaystyle \varepsilon }
(proportional deformation) in the linear elastic region of a material and is determined using the formula:
E
=
σ
ε
{\displaystyle E={\frac {\sigma }{\varepsilon }}}
Young's moduli are typically so large that they are expressed not in pascals but in gigapascals (GPa).
Although Young's modulus is named after the 19th-century British scientist Thomas Young, the concept was developed in 1727 by Leonhard Euler. The first experiments that used the concept of Young's modulus in its current form were performed by the Italian scientist Giordano Riccati in 1782, pre-dating Young's work by 25 years. The term modulus is derived from the Latin root term modus which means measure.
My answer is (B) since it has the highest slope for the straight line part of the graph but the answer key is (A). Is it because the slope of graph B will decrease until the value less than slope A? So we don't only consider the straight line part but the whole graph?
Thanks
We need to find a single wire supporting the load. But, when I think about it there can so many different types of materials we could use for the single wire and each of these single wires would have a different Young's Modulus. So, I don't get what equivalent means here?
Anyways, I get the...
Hi. I am in the IB and am looking at doing a physics IA (internal assessment) on Young's modulus on an elastic material. I was thinking of doing it on the the stretchy snakes like the candy. What would I need to cover in this?
Hi all,
I'm a little confused about something.
Force-extension graphs and stress-strain graphs are always both straight lines up until the limit of proportionality, implying both the spring constant and the Young modulus are constant up until then.
For a force-extension graph, Hooke's Law...
Homework Statement
Superman pulls on a steel post to trap a supervillian. The post has a cross-sectional area of 30cm^2 and a length of 2m. If Superman applies a force of 6X10^6N by how much is the length of the post increased?
A) 2mm
B) 7mm
C) 1.2cm
D) 1.7cm
E) 2cm
Homework Equations...
Homework Statement
1) calculate the longest
length of steel wire that can hang vertically without breaking
.breaking stress for steel=7.982*10^8N/m^2 and density of
steel(d)=8.1*10^3kg/m^3.2)A bar of mass m and length l is hanging from a point A as shown in the figure.Find the increase...
Hello everyone, nice to be here.
I am going to calculate the young modulus of 3 layers of carbon fiber laminar composite
For example:
1st: 12K plain wave carbon fiber in 0 degree
2nd:3K till wave carbon fiber in 45deg
3rd:12K plain wave carbon fiber in 0 degree
How can I approach to calculate...
Q: Calculate the force (in N) a piano tuner applies to stretch a steel piano wire 8.50 mm, if the wire is originally 0.850 mm in diameter and 1.35 m long. (Young's modulus for steel is 20.0 ✕ 1010 Pa.)
Work F=Y*A*change in L/L_0
I have no idea what is L_0 and L_f? Please help me.
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...
My Aim is to determine the youngs modulus of aluminium from the data we get from tensile strength test.
The attached excel sheet contains all the data i am using such as elongation,load value(which is in kN i have converted to N for calculating Stress)
For stress,
I am using the formula...
Is it true for all material that if young's modulus is high then melting point will be high and coeff of thermal expansion will be lower? Any example that doesn't follow the above statement.
Many Thanks
Hello everybody. I've measured the Young Modulus of PDMS samples both in compression and in tension. From compressive tests I get a Modulus twice as big as the one I get from tensile tests.
Is it normal to get two different values for Young Modulus using tensile or compressive tests? Do you...
Homework Statement
A rod is made up as shown [pic attached]
Both have same cross-sectional area. Ep and En are Young modulus.
The rod breaks when total extension = 3.0mm
Greatest tensile stress that can be applied before rod breaks?
Homework Equations
Young modulus = stress / strain
The...
Quoted from my book:
"The graph of ΔL against F has gradient L/EA, so the Young modulus E is equal to L(A x gradient)."
E is (stress/strain).
I don't understand that sentence. If I substitute the gradient into E= L(A x gradient), then
E= L(A)(L/EA)
E= L(L/E)
E= L^2 /E
E square = L square...
Question 1:
--> Why both the wires are suspended from the same rigid support in this experiment?
Question 2:
-->Why both the wires are taken of the same material?
Homework Statement
A three-legged stool has one leg of aluminium (E = 7 x 1010 Pa), one copper (E = 11 x 1010 Pa) and one of steel (E = 20 x 1010) Pa. The legs have the same dimensions. If the load on the stool is at the exact center,
a. Which leg is under the greatest stress? Explain why
b...
Hi, dear all,
Recently face some controversial issue with my supervisor and i cannot convince my self too.
is it time varying elastance equal to time varying young modulus?
Young modulus unit is Pa, however, elastance value is mmHg/ml, is both of them are equal?
Young's modulus, also...
Homework Statement
Calculate the stress in a wire of diameter 0.35mm when the tension in the wire is 50N.
Homework Equations
Stress=F/A
The Attempt at a Solution
0.25/2=0.125
0.125/100=1.25x10"-3
Pi x 0.00125"2 = 1.542x10"-5
50/1.542x10"-5 = 3242542.153 Pa
Are my...
I have started a home study course in mechanical engineering, I now realize that I should have started with a math’s course but any way I have a question that I could do with some help with. A designer wishes to calculate the thickness (diameter) of a steel cable for suspending a passenger lift...
out of interest does cross sectional area change when a force is applied (lets say I had a wire and I applied a force to it, the wire would stretch ) does its cross sectional area change
Homework Statement
A particle of mass m is attached to one end of a light elastic string of natural length a and modulus mg, the other end of the sting is attached to a fixed point O on smooth horizontal surface. The particle is released from rest at horizontal distance a+L from O...
Hi I have a problem with the following question:
A steel violin string has a cross-sectional area of 0.2*10^-6 m^2 and is under tension 83N. If its length under tension is 35cm, find its original length.
I can not seem to solve the question without needing the value of young modulus...
in young modulus of a metal bar , we have a horizontal bar on one side we attach some weight so there is some change in angle but no change in length then why it is called young modulus?
in the following question, how do i find the changle in AB, the change in AD and the change in AC?
http://lh4.ggpht.com/_H4Iz7SmBrbk/Sv_hYT83rYI/AAAAAAAAB8s/7l5YRXMxVfQ/s912/Capture.JP what i have done is used the following
\sigmaxx=E*\epsilonxx
\deltaAB=\epsilonAB*AB
since AB is on the x...
Homework Statement
find the young modulus of copper through calculating the stress and strain, plotting on a graph and finding
the gradient of the linear part of the graph
Homework Equations
ym=stress/strain
stress=force/ area
strain= extension/length
The Attempt at a Solution...
Hi everyone,
I want to know what the difference between bulk modulus and young modulus is? In some papers, it seems that they have compared the value of these two as if they are the same.
Could anyone help me with this regard?
Regards,
Sara
Homework Statement
The cables of length 70m supporting a lift consist of two steel ropes each of 100 strangs giving a total cross sectional area of 1.0 x 10^-4 m^2. Consider a full lift to carry 8 passengers of average mass 75kg. Calculate by how much an empty lift moves down when it is...
Homework Statement
The problem is that I do not have a way of making a nylon rope young modulus stress/strain graph I did not know is anyone would be able to help me obtain the information on the stress and strain or if your feeling really nice make me up a graph!
young modulus = stress...
My cwk is investigating the youngs modulus of a scooby. A scooby is a hollow plastic string like thing. My experiment used the pulley clamped to the bench method and attaching weights.
I have my results and have worked out the change in area for each load and have a graph of stesslog10 vs...
Urgent help! Young modulus how to hold masses
In a young modulus experiment Ieed to holdp the msss i decdied to use hole puncher at both ends I relsiedthis woodnt work becaue strech properly
I culd use bull dogclips but masses may make it fall off
Wha do u nomally use in a young modulus...