Lecture 0: Introduction and
Overview of Course
Serway
and
Vuille
Ch. 1
Outline
•
What is physics?
•
Outline of course
•
SI units and conversion of units
•
Dimensional analysis
•
Uncertainty and significant figures
Introduction to Physics
•
The
goal
of
physics
is
to
provide
an
understanding
of
the
physical
world
by
developing
theories
based
on
experiments
.
•
A
physical
theory
describes
how
a
given
physical
system
works,
makes
prediction
about
the
physical
system,
and
can
be
falsified
by
observations
and
experiments
.
Introduction to Physics
•
The
common
subfields
of
physics
are
–
Classical
Mechanics
–
Thermodynamics
–
Electromagnetism
–
Quantum
Mechanics
–
Atomic
and
Nuclear
Physics
–
Relativity
Course Outline
•
Motion and Kinematics
•
Newton’s Laws of Motion and Dynamics
•
Energy and Energy Conservation
•
Momentum and Collisions
•
Newtonian Gravitation
•
Rotational Dynamics
•
Fluid Mechanics and Fluid Dynamics
•
Vibrations, Waves, and Sound
•
Thermal Physics
Motion and Kinematics
•
The
study
of
motion
without
regards
to
its
causes
is
called
kinematics
•
Important
topics
are
–
Displacement,
velocity,
and
acceleration
–
Freely
falling
objects
–
Projectile
motion
Newton’s Laws and Dynamics
•
The
study
of
motion
and
its
physical
causes
is
called
dynamics
•
Important
topics
are
–
Newton’s
laws
of
motion
–
Statics
and
equilibrium
–
Forces
of
friction
Energy and Work
•
Energy
is
one
of
the
most
important
concepts
in
science
and
is
present
in
a
variety
of
forms
•
Important
topics
are
–
Work
and
kinetic
energy
–
Potential
energy
–
Conservation
of
mechanical
energy
–
Power
Momentum and Collisions
•
The
concept
of
momentum
is
important
in
analyzing
multi

component
systems
•
Important
topics
are
–
Momentum
and
impulse
–
Elastic
and
inelastic
collisions
–
Rocket
propulsion
Newtonian Gravitation
•
Rotational
motion,
when
combined
with
Newton’s
law
of
universal
gravitation,
can
explain
certain
facts
about
space
travel,
satellite
motion,
and
the
motion
of
astronomical
objects
.
Rotational Dynamics
•
Rotational
dynamics
is
important
when
the
point
of
application
of
a
force
is
important
.
•
Important
topics
are
–
Torque
and
moment
of
inertia
–
Rotational
equilibrium
–
Rotational
kinetic
energy
–
Angular
momentum
Fluid Mechanics and Fluid Dynamics
•
An
understanding
of
the
fundamental
properties
of
fluids
is
important
in
all
the
sciences,
in
engineering,
and
in
medicine
.
•
Important
topics
are
–
Density
and
pressure
–
Buoyant
force
and
Archimedes’
principle
–
Bernoulli’s
equation
–
Poiseuille’s
law
–
Diffusion
Vibrations and Waves
•
Periodic
motion
(from
masses
on
springs
to
vibrations
of
atoms)
is
one
of
the
most
important
kinds
of
physical
behavior
and
cause
disturbances
that
move
through
a
medium
in
the
form
of
waves
.
•
Important
topics
are
–
Hooke’s
law
–
Simple
harmonic
motion
–
Properties
of
waves
Sound
•
Sound
waves
are
the
most
important
example
of
longitudinal
waves
and
examining
sound
waves
help
us
understand
how
we
hear
.
•
Important
topics
are
–
Properties
of
sound
–
Doppler
effect
–
Forced
vibrations
and
resonance
Thermal Physics
•
Thermal
physics
is
the
study
of
temperature
heat
and
how
they
affect
matter
.
•
Thermal
physics
requires
careful
definition
of
the
concepts
of
temperature,
heat,
and
internal
energy
.
•
Important
topics
–
Kinetic
theory
of
gases
–
Thermal
expansion
–
Latent
heat
and
internal
energy
–
Laws
of
thermodynamics
SI Units
•
The
basic
laws
of
physics
can
be
described
in
terms
of
fundamental
physical
quantities
.
–
In
mechanics,
all
physical
quantities
can
be
derived
by
length
(L),
mass
(M),
and
time
(T)
.
•
To
properly
communicate
the
result
of
a
measurement
of
a
certain
physical
quantity,
a
unit
for
the
quantity
must
be
defined
.
•
A
standard
system
of
units
for
the
fundamental
quantities
of
science
are
called
SI
units
(or
mks
units
)
.
SI Units
•
The
SI
units
for
length,
mass,
and
time
are
meter
,
kilogram
,
and
second
,
respectively
.
SI Units
•
The
SI
units
for
length,
mass,
and
time
are
meter
,
kilogram
,
and
second
,
respectively
.
Conversion of Units
•
Usually,
it’s
necessary
to
convert
units
from
one
system
to
another
by
using
conversion
factors
.
Conversion of Units
•
Ex
:
Convert
15
inches
to
centimeters
(cm)
and
meters
(m)
.
15
𝑖
∗
2
.
54
𝑐
1
𝑖
=
38
.
1
𝑐
38
.
1
𝑐
∗
0
.
01
1
𝑐
=
0
.
381
Conversion of Units
•
Ex
:
Convert
64
.
0
miles
per
hour
(mi/h)
to
meters
per
second
(m/s)
.
64
𝑖
ℎ
∗
1
ℎ
3600
∗
1
609
1
𝑖
=
28
.
60
Dimensional Analysis
•
In
physics,
dimension
denotes
the
physical
nature
of
a
quantity
.
–
Ex
:
Distance
has
the
dimensions
of
length
•
Brackets
will
be
used
to
denote
the
dimensions
of
a
physical
quantity
–
Ex
:
The
dimensions
of
volume
V
are
[V]
=
L
3
•
One
way
to
analyze
mathematical
expressions
that
relate
different
physical
quantities
is
through
dimensional
analysis
Dimensional Analysis
•
Dimensional
analysis
makes
use
of
the
fact
that
dimensions
can
be
treated
as
algebraic
quantities
.
•
In
order
for
any
equation
to
be
correct,
it
must
be
dimensionally
consistent
,
i
.
e
.
the
terms
on
the
opposite
side
of
an
equation
must
have
the
same
dimensions
.
•
Dimensional
analysis
is
a
quick
way
to
check
the
consistency
of
the
results
from
problem
solving
.
Dimensional Analysis
•
Ex
:
What
are
the
dimensions
for
velocity
v
and
acceleration
a
?
𝑣
=
𝐿
𝑇
𝑎
=
𝑣
𝑇
=
𝐿
/
𝑇
𝑇
=
𝐿
/
𝑇
2
Dimensional Analysis
•
Ex
:
Which
of
the
following
equations
are
dimensionally
consistent?
Assume
that
r
has
dimensions
of
length
=
1
2
𝑎
2
=
𝐿
𝑎
2
=
𝐿
𝑇
2
∙
𝑇
2
=
𝐿
•
The
equation
is
dimensionally
consistent
Dimensional Analysis
•
Ex
:
Which
of
the
following
equations
are
dimensionally
consistent?
Assume
that
r
has
dimensions
of
length
𝑣
=
𝑎
2
𝑣
=
𝐿
𝑇
𝑎
2
=
𝐿
𝑇
2
∙
𝑇
2
=
𝐿
•
The
equation
is
not
dimensionally
consistent
Dimensional Analysis
•
Ex
:
Which
of
the
following
equations
are
dimensionally
consistent?
Assume
that
r
has
dimensions
of
length
𝑎
=
𝑣
2
/
𝑎
=
𝐿
𝑇
2
𝑣
2
=
𝐿
2
/
𝑇
2
𝐿
=
𝐿
𝑇
2
•
The
equation
is
dimensionally
consistent
Dimensional Analysis
•
Ex
:
Which
of
the
following
equations
are
dimensionally
consistent?
Assume
that
r
has
dimensions
of
length
=
𝑣
2
/
𝑎
=
𝐿
𝑣
2
𝑎
=
𝐿
2
/
𝑇
2
𝐿
/
𝑇
2
=
𝐿
•
The
equation
is
not
dimensionally
consistent
Uncertainty and Significant Figures
•
In
practice,
we
use
significant
figures
to
convey
the
level
of
accuracy
associated
with
a
given
measurement
.
•
A
significant
figure
is
a
reliably
known
figure
(other
than
a
zero)
used
to
locate
a
decimal
point
.
•
In
calculations,
the
method
of
significant
figures
is
used
to
indicate
the
approximate
number
of
digits
that
should
be
retained
at
the
end
of
a
calculation
.
Uncertainty and Significant Figures
•
In
multiplying
(dividing)
2
+
quantities,
the
number
of
significant
figures
in
the
final
product
(quotient)
is
the
same
as
the
number
of
significant
figures
in
the
least
accurate
of
the
factors
being
combined
.
•
When
numbers
are
added
(subtracted),
the
number
of
decimal
places
in
the
results
should
equal
the
smallest
number
of
decimal
places
of
any
term
in
the
sum
(difference)
.
•
Scientific
notation
is
used
to
indicate
the
number
of
significant
figures
Significant Figures
•
Ex
:
A
rectangular
airstrip
measures
32
.
30
m
by
210
m
with
the
width
measured
more
accurately
than
the
length
.
Find
the
area,
taking
into
account
significant
figures
.
𝐴
=
𝐿
∗
=
32
.
30
∗
210
=
6
.
8
∗
10
3
2
Significant Figures
•
Ex
:
The
edges
of
a
shoebox
are
measured
by
11
.
4
cm,
17
.
8
cm,
and
29
cm
.
Determine
the
volume
of
the
box
retaining
the
proper
number
of
significant
figures
in
your
answer
.
=
𝐿
∗
∗
𝐻
=
11
.
4
𝑐
∗
17
.
8
𝑐
∗
29
𝑐
=
5
.
9
∗
10
3
𝑐
3
Trigonometry
•
See
Appendix
A
.
5
and
section
1
.
7

1
.
8
in
your
textbook
for
a
quick
review
on
trigonometry
.
•
For
a
more
extensive
review,
see
the
following
link
:
•
http
:
//tutorial
.
math
.
lamar
.
ed
u/Extras/AlgebraTrigReview/
AlgebraTrigIntro
.
aspx
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