When you become a practicing engineer,you will find out that you don’t stop learn-
ing new things even after obtaining your engineering degree.For example,you may
work on a project in which the noise of a machine is a concern,and you may be asked
to come up with ways to reduce the level of noise.It may be the case that during the
four or five years of your engineering education,you did not take a class in noise con-
trol.Considering your lack of understanding and background in noise reduction,you
may first try to find someone who specializes in noise control who could solve the
problem for you.But your supervisor may tell you that because of budget constraints
and because this is a one-time project,you must come up with a reasonable solution
yourself.Therefore,you will have to learn something new and learn fast.If you have
a good grasp of underlying engineering concepts and fundamentals,the learning
process could be fun and quick.The point of this story is that during the next four
years you need to make sure that you learn the fundamentals well.
TABLE 6.7 Fundamental Dimensions and How They Are Used in Defining Variables that Are Used in Engineering Analysis and Design
Fundamental
Dimension Related Engineering Variables
Length (L) Radian , Area (L^2 ) Volume (L^3 ) Area moment
[Chapter 7] Strain of inertia (L^4 )
Time (t) Angular speed ,
[Chapter 8] Angular acceleration Volume flow rate
Linear speed ,
Linear acceleration
Mass (M) Mass flow rate , Density ,
[Chapter 9] Momentum Specific volume
Kinetic energy
Force (F) Moment (LF), Pressure ,
[Chapter 10] Work, energy (FL), Stress , 1
F
L^22
1
F
L^22
1
ML^2
t^22
1
L^3
(^1) M 2
ML
t^2
1
M
L
1 32
M
t^2
1
L
t^22
1
L
t^2
1
L^3
(^1) t 2
1
t^22
1
1
t^2
1
L
L^2
1
L
L^2
Linear impulse (Ft), Modulus of Specific weight ,
Power elasticity ,
Modulus of
rigidity
Temperature (T) Linear thermal expansion Volume thermal
[Chapter 11] expansion
Specific heat
Electric Current (I) Charge (It) Current density
[Chapter 12] 1
I
L
22
1
FL
MT^2
1
L^3
(^1) L (^3) T 2
L
LT^2 ,
1
F
L^22
1
F
(^1) L 22
FL
t^2
1
F
L^32
160
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