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Problem Set for MATLAB Essentials

Determine the value of each of the following.

6 7 4 2 2 4

>>(6*7)+4^2-2^4 (ans = 42)

3 2 2 3 4 5 5 4 64 0.5 5 2 4 5 5 6 7 8

>>((3^2+2^3)/(4^5-5^4))+((sqrt(64)-5^2)/(4^5+5^6+7^8)) (ans = 0.0426)

10 2 10 5

>>log10(10^2)+10^5 (ans = 100002)

2 2 3 2

>>exp(2)+2^3-log(exp(2)) (ans = 13.3891)

2 4

>>sin(2*pi)+cos(pi/4) (ans = 0.7071)

3 270 270 3

>>tan(pi/3)+cos(270*pi/180)+sin(270*pi/180)+cos(pi/3) (ans = 1.2321)

Solve the following system of equations:
2 x 4 y 1
x 5 y 2

>>A=[2 4; 1 5] A =2 4 1 5>>B=[1; 2] B =1 2>>Solution=A\B Solution =-0.5000 0.5000

Evaluate y at 5.
y 4 x 4 3 x 2 x

>>p=[4 0 3 -1 0] p =4 0 3 -1 0>>polyval(p,5) ans =2570>>

Given below is Load-Gage Length data for a type 304 stainless steel that underwent a tensile test. Original specimen diameter is 12.7 mm. Introduction to Materials Science for Engineers by J. F. Shackelford, Macmillan Publishing Company. © 1985, (p.304)

Load [N] Gage Length [mm]
0.000 50.8000
4890 50.8102
9779 50.8203
14670 50.8305
19560 50.8406
24450 50.8508
27620 50.8610
29390 50.8711
32680 50.9016
33950 50.9270
34580 50.9524
35220 50.9778
35720 51.0032
40540 51.816
48390 53.340
59030 55.880
65870 58.420
69420 60.960
69670 (maximum) 61.468
68150 63.500
60810 (fracture) 66.040 (after fracture)
σ P A , where P is the load [N] on the sample with an original cross-sectional area A [ m 2 ] and the engineering strain is defined as ε Δl l , where Δl is the change in length and l is the initial length.

Compute the stress and strain values for each of the measurements obtained in the tensile test. Data available for download.

First, we need to enter the data sets. Because it is rather a large table, using Variable Editor is more convenient. See the figures below:

Load
Load in Newtons
Length
Extension length in mm.

Next, we will calculate the cross-sectional area. Area=pi/4*(0.0127^2) Area =1.2668e-004

Now, we can find the Stress values with the following, note that we are obtaining results in MPa: Sigma=(Load_N./Area)*10^(-6) Sigma =0 38.602277.1964 115.8065154.4086 193.0108218.0351 232.0076257.9792 268.0047272.9780 278.0302281.9773 320.0269381.9955 465.9888519.9844 548.0085549.9820 537.9830480.0403

For strain calculation, we will first find the change in length: Delta_L=Length_mm-50.800 Delta_L =0 0.01020.0203 0.03050.0406 0.05080.0610 0.07110.1016 0.12700.1524 0.17780.2032 1.01602.5400 5.08007.6200 10.160010.6680 12.700015.2400

Now we can determine Strain with the following: Epsilon=Delta_L./50.800 Epsilon =0 0.00020.0004 0.00060.0008 0.00100.0012 0.00140.0020 0.00250.0030 0.00350.0040 0.02000.0500 0.10000.1500 0.20000.2100 0.25000.3000

The final results can be tabulated as foolows: [Sigma Epsilon] ans =0 0 38.6022 0.000277.1964 0.0004 115.8065 0.0006154.4086 0.0008 193.0108 0.0010218.0351 0.0012 232.0076 0.0014257.9792 0.0020 268.0047 0.0025272.9780 0.0030 278.0302 0.0035281.9773 0.0040 320.0269 0.0200381.9955 0.0500 465.9888 0.1000519.9844 0.1500 548.0085 0.2000549.9820 0.2100 537.9830 0.2500480.0403 0.3000

Questions & Answers

if three forces F1.f2 .f3 act at a point on a Cartesian plane in the daigram .....so if the question says write down the x and y components ..... I really don't understand
Syamthanda Reply
hey , can you please explain oxidation reaction & redox ?
Boitumelo Reply
hey , can you please explain oxidation reaction and redox ?
Boitumelo
for grade 12 or grade 11?
Sibulele
the value of V1 and V2
Tumelo Reply
advantages of electrons in a circuit
Rethabile Reply
we're do you find electromagnetism past papers
Ntombifuthi
what a normal force
Tholulwazi Reply
it is the force or component of the force that the surface exert on an object incontact with it and which acts perpendicular to the surface
Sihle
what is physics?
Petrus Reply
what is the half reaction of Potassium and chlorine
Anna Reply
how to calculate coefficient of static friction
Lisa Reply
how to calculate static friction
Lisa
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Tumelo
how to calculate the magnitude of horizontal component of the applied force
Mogano
How to calculate force
Monambi
a structure of a thermocouple used to measure inner temperature
Anna Reply
a fixed gas of a mass is held at standard pressure temperature of 15 degrees Celsius .Calculate the temperature of the gas in Celsius if the pressure is changed to 2×10 to the power 4
Amahle Reply
How is energy being used in bonding?
Raymond Reply
what is acceleration
Syamthanda Reply
a rate of change in velocity of an object whith respect to time
Khuthadzo
how can we find the moment of torque of a circular object
Kidist
Acceleration is a rate of change in velocity.
Justice
t =r×f
Khuthadzo
how to calculate tension by substitution
Precious Reply
hi
Shongi
hi
Leago
use fnet method. how many obects are being calculated ?
Khuthadzo
khuthadzo hii
Hulisani
how to calculate acceleration and tension force
Lungile Reply
you use Fnet equals ma , newtoms second law formula
Masego
please help me with vectors in two dimensions
Mulaudzi Reply
how to calculate normal force
Mulaudzi
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Source:  OpenStax, A brief introduction to engineering computation with matlab. OpenStax CNX. Nov 17, 2015 Download for free at http://legacy.cnx.org/content/col11371/1.11
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