Transcript Introduction to Modern Physics PHYX 2710

Physics of Technology
PHYS 1800
Lecture 1
Introduction
Section 0
Lecture 1
Slide 1
Introduction
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
INTRODUCTION
Lecture 1 Slide 1
Physics of Technology
PHYS 1800
Introduction
Class Administration
and
Section 0 Lecture 1 Slide 2
Syllabus
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
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Lecture 1 Slide 2
PHYSICS OF TECHNOLOGY - PHYS 1800
Spring Semester 2008
Course: Designed for non-physics majors.
Goal: To help you develop a good understanding of everyday
physics, i.e. the world around us.
Help: You develop an enjoyment in understanding and explaining
everyday phenomena.
Not aimed at simply accumulating a bunch of facts!
Section 0 Lecture 1 Slide 3
You Introduction
will Discoverthat learning to develop your own physical
explanations will be most gratifying and will give you a much better
appreciation of nature.
INTRODUCTION TO Modern Physics PHYX 2710
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Spring 2009
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Lecture 1 Slide 3
PHYSICS OF TECHNOLOGY
Class:
MWF
Recitations:
T
Labs/Demos
10:30 - 11:20
BUS 318
1:30-2:45
ESLC 53
H
1:30-2:45
ESLC 53
Exams scheduled H 1:30-2:45 in ESLC 53
Instructor:
J.R. Dennison
797-2936
Office Hours:
[email protected]
MWF 11:30-12:30
Assistant Instructor: Jennifer Roth
363-4704
Introduction
Section 0
Class
Web Site:
SER 222D
SER 1
[email protected]
Lecture
1 Slide 4
http://www.physics.usu.edu/
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 4
PHYSICS OF TECHNOLOGY
Objectives: This course provides a conceptual introduction
to physics with three primary goals:
(1) to gain physical intuition
(2) to develop problem solving skills
(3) to learn to apply some basic physics principles to
everyday phenomena.
Texts:
W.Thomas Griffith, The Physics of Everyday Phenomena,
A Conceptual Introduction to Physics, 5th or 6thEd
(McGraw Hill, 2007, 2009) REQUIRED.
Introduction
Section 0
Lecture 1
Slide 5
Prerequisites:
College Algebra (Math 1050),
Trigonometry (Math 1060).
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Lecture 1 Slide 5
PHYSICS OF TECHNOLOGY
Where to get help:
If you find yourself confused on a particular topic in this course or
are spending more than 10-15 min on the main homework problems
you should seek help by:
Reviewing the text and looking over other example problems. (Solutions
to odd numbered problems are given in the back of text.)
Talk with colleagues in your class and have them explain things to you
(rather than simply solving the problem for you).
Physics Learning center offers tutorial services in SER 217.
Ask questions in the Recitation class (be prepared to show your work
and explain where the problem arises). This will lead to a better
Introduction Section 0 Lecture 1 Slide 6
understanding for you and a positive discussion for the whole class.
Seek help from the class Instructor or the Assistant Instructor during
designated office hours (or other times as available).
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 6
PHYSICS OF TECHNOLOGY
Lectures (BUS 318):
Will focus on basic physical concepts and their
application in our every day world.
To better assist the student they will augment and follow
the textbook development but will not cover all the text
material in detail.
The student is advised to read the text (as indicated in
the attached syllabus breakdown) prior to coming to
each lecture to be more familiar with the topics
discussed.
Introduction Section 0 Lecture 1 Slide 7
Lecture notes available on Web at: www.physics.usu.edu,
then follow: Class Website, Phys 1800….
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PHYSICS OF TECHNOLOGY
Laboratory (ESLC 053):
To aid the understanding of the physical concepts a laboratory demonstration class
will be given every Thursday (1:30 -2:45 pm).
Numerous experiments will be performed to illustrate the principles discussed in the
lectures and to help develop your understanding.
No direct credit will be given for attending these demonstration labs but the homework
and exam questions will often draw upon these experiments and you are strongly
advised to attend the demonstrations.
Note: The $10 fee is used to upkeep the laboratory demonstration equipment used in
this class.
Recitation (ESLC 053):
A recitation class will be given every Thursday (1:30-2:45 pm). They are designed to
review and reinforce the material presented in the lectures and in the textbook
Introduction Section 0 Lecture 1 Slide 8
and will act as a forum for developing your problem solving skills.
Recitation classes provide an excellent opportunity for you to discuss your homework
problems and applications of the class material to every day life.
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 8
PHYSICS OF TECHNOLOGY
Homework:
Assignment problems based on the class and laboratory material will be
given out at the Friday class and should be returned at the beginning
of class on the following Friday (see Assignment Sheet for exact
schedule).
You are encouraged to discuss the homework assignment with others and
to work together solving the problems. However, it is a violation of USU
rules to copy someone else’s homework. Your homework must be in
your own words and must not duplicate the work of other students.
Homework Format:
There will be 12 sets of homework each of which will consist of several
short answer questions as well as some basic problems.
Introduction Section 0 Lecture 1 Slide 9
Each homework is worth up to 20 points. (To get credit for a problem you
must show your work and make a reasonable attempt to solve it.)
Only your top 10 homework scores will be counted in your grade.
Homework must be handed in on time.
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Lecture 1 Slide 9
PHYSICS OF TECHNOLOGY
Homework Grading:
No credit will be given for late homework; it will be counted as one
of the two scores that are dropped.
Up to two additional Bonus Questions will be given out with each
homework assignment. These are a little more challenging (but
quite doable) problems that are intended to expand your physics
comprehension and problem solving skills.
Bonus questions are optional and must be handed in with your
homework. You may receive an additional score of up 25% extra
credit for these optional questions.
Introduction
Section 0
Lecture 1
Slide 10
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 10
PHYSICS OF TECHNOLOGY
Class Grading:
Your final grade will be based on your homework, and four
exams.
Homework (20%): This is an essential part of your studies and is
key to doing well in the class. A large fraction of the exam
questions will be based on the homework and laboratory
problems.
In-Class Tests (20% each):
There are three in-class exams. These will be scheduled during
lab/demo time on Thursdays (see Syllabus). Each test will be
closed-book and will be based on the recent topics covered in
class and on the homework and laboratory demonstrations.
Introduction Section 0 Lecture 1 Slide 11
Each test will consist of several multiple choice questions, short
answer questions and some basic numerical problems. A list of
relevant formulas will be provided.
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Lecture 1 Slide 11
PHYSICS OF TECHNOLOGY
Final Exam (20%):
The final exam is not cumulative but will follow the format of the
previous three in-class exams (Friday: May 1st at 09:30-11:20am).
Make-Up Exams:
These will not be given unless there are extremely compelling
reasons or illness, in which case a Doctor’s letter will be required.
ID: You should be prepared to present a photo ID at the time of
Introduction
each exam.
Section 0
Lecture 1
Slide 12
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Lecture 1 Slide 12
PHYSICS OF TECHNOLOGY
Spring 2009 Assignment Sheet
Date
Day
Lecture
Chapter
Jan 5
M
Class Admin: Intro.Physics Phenomena
1
6
T
Problem solving and math
App. B, C
7
W
Units, Scalars, Vectors,
1
9
F*
Speed and Velocity
2
Jan 12
M
Acceleration
2
14
W
Free Falling Objects
3
16
F*
Projectile Motion
3
Jan 19
M
Martin Luther King
No Class
21
W
Newton’s Laws
4
23
F*
Mass and Weight
4
Jan 26
M
Motion with Friction
4
28
W
Review
1-4
1-4
29
Th
Test 1
30
F
Circular Motion
5
Feb 2
M
Planetary Motion and Gravity
5
4
W
Energy
6
6
F*
Harmonic Motion
6
Feb 9
M
Momentum
7
11
W
Impulse and Collisions
7
13Introduction
F*
Rotational
Motion 1 Slide 13
8
Section
0 Lecture
Feb 16
M
Presidents Day
No Class
17
Tu
Angular Momentum (Virtual Monday)
8
18
W
Review
5-8
19
5-8
H
Test 2
INTRODUCTION TO Modern Physics PHYX 2710
20
F*
Static Fluids, Pressure
9
Fall 2004
Feb 23
M
Flotation
9
25
W
Fluids in Motion
9
27
F*
Temperature and Heat
10
Mar 2
M
First Law of Thermodynamics
10
Physics of Technology—PHYS 1800
4
W Spring 2009Heat flow and Greenhouse Effect
10
INTRODUCTION
*Homework
Handout
6
F*
Climate Change
-
Homework Due
-
1
2
3
4
5
-
6
Lecture 1 Slide 13
7
6
F*
Feb 9
M
11
W
13
F*
Feb 16
M
17
Tu
18
W
19
H
20
F*
Feb 23
M
25
W
27
F*
Mar 2
M
4
W
6
F*
Mar 9-13
M-F
Mar 16
M
18
W
20
F*
Mar 23
M
25
W
26
H
27
F*
Mar 30
M
Apr 1
W
3
F
Apr 6
M
8
W
10
F*
Apr 13
M
15
W
Introduction
17
F*
Apr 20
M
22
W
24
F
May 1
F
Harmonic Motion
Momentum
Impulse and Collisions
Rotational Motion
Presidents Day
Angular Momentum (Virtual Monday)
Review
Test 2
Static Fluids, Pressure
Flotation
Fluids in Motion
Temperature and Heat
First Law of Thermodynamics
Heat flow and Greenhouse Effect
Climate Change
Spring Break
Heat Engines
Power and Refrigeration
Electric Charge
Electric Fields and Electric Potential
Review
Test 3
Electric Circuits
Magnetic Force Review
Electromagnets
Motors and Generators
Making Waves
Sound Waves
E-M Waves, Light and Color
Mirrors and Reflections
Refraction and Lenses
Section
0 and
Lecture
1 Slide 14
Telescopes
Microscopes
Review
Seeing Atoms
The really BIG & the really small
Final Exam: 09:30-11:20am
6
7
7
8
No Class
8
5-8
5-8
9
9
9
10
10
10
No Classes
11
11
12
12
13
9-12
13
14
9-12
14
15
15
16
17
17
17
1-17
18 (not on test)
21 (not on test)
4
PHYSICS OF TECHNOLOGY
5
Spring 2009 Assignment Sheet
-
6
7
8
-
9
10
11
No test week
12
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
*Homework Handout
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INTRODUCTION
Lecture 1 Slide 14
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Introduction
Section 0
Introduction
to
Lecture 1 Slide 15
Physics
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
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Spring 2009
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Lecture 1 Slide 15
What is Physics?
“Study of the basic nature of matter and the
interactions that govern its behavior.”
BORING!!!
“How Stuff Works.”
True, but vague.
“Common Sense Approach to How Things Work”
(with units!)
Introduction Section 0 Lecture 1 Slide 16
Common Sense—A minimal set of simple, straightforward
guides.
Units—Predictions on a quantitative level
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 16
Scientific Method:
Leads to new discoveries → how scientific
progress is made!
Careful measurements,
Experiments
Empirical
laws,
Introduction Section 0
Generalization
Hypothesis,
Lecture 1
Slide 17
Theory
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
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Lecture 1 Slide 17
Introduction
Section 0
Lecture 1
Slide 18
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 18
Introduction
Section 0
Lecture 1
Slide 19
James Webb Space Telescope
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
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Lecture 1 Slide 19
Why study everyday phenomena?
The same physical principles that govern our
everyday experiences also govern the entire
universe
– A bicycle wheel, an atom, and a galaxy all operate
according to laws for angular momentum.
Introduction
Section 0
Lecture 1
Slide 20
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 20
What are the major subfields in Physics?
Classical Physics (pre 20th century)
–
–
–
–
Mechanics → forces, motion
Thermodynamics → heat, temperature
Electricity and magnetism → charge, currents
Optics → light, lenses, telescopes
Modern Physics (20th century)
– Atomic and nuclear
→ radioactivity, atomic power
– Quantum mechanics
} → basic structure matter
– Particle
physics
Introduction Section 0 Lecture 1 Slide 21
– Condensed matter → solids and liquids, computers,
lasers
– Relativity, Cosmology → universe, life!
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 21
State of Physics cira 1895
Conservation Laws
Electricity & Magnetism • Energy
Statistical Mechanics
• 3 Laws of Thermodynamics
• Kinetic Theory
Maxwell Equations (c 1880)
• Gauss’ Law
•Faraday’s Law
•Ampere’s Law
•No magnetic monopoles
• Linear & Angular Momentum
Mechanics (Gravity)
Newton’s Laws (c 1640)
1-Law of inertia
2-F=ma
3-Equal and opposite reactions
Introduction
Section 0
Lecture 1
Slide 22
INTRODUCTION TO Modern Physics PHYX 2710
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Spring 2009
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Lecture 1 Slide 22
Limits of pre-Modern Physics
Dimension Range of
Applicability
Range of Application
Length
10-6 to 10+8 m
Smoke particle (Brownian
Motion) to the solar system
Mass
10-9 to 10+31 kg
Dust particles to solar mass
Time
10+10 to 10+17 sec-1
10-3 to 10+9 sec
Microwave to UV light
Smallest timing increments
(msec) to celestial motions
(centuries)
Lecture 1
-6 to 010+5
10Section
m/s
Small particles to celestial
motion
Velocity
Introduction
Slide 23
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 23
State of Physics cira 1895
Lord Kelvin—arguably the greatest
physicist of his day:
• Strong opponent of existence of atoms
•“There is nothing new to be discovered in
physics now. All that remains is more and more
precise measurement."
Albert A Michleson—the first US
Physics Nobel laureate
•“The grand underlying principles have been
firmly established...further truths of physics are to
be lookedIntroduction
for in the
sixth place of decimals"
Section 0 Lecture 1 Slide 24
(Science, 1892)
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 24
Inconsistencies in Physics cira 1900
Statistical Mechanics
• Boltzmann Distribution
• Entropy and counting states
Electricity & Magnetism
• Medium for propagation of light
• Obeys Lorentz transformation
•
•
•
•
Mechanics (Gravity)
• Discrete atomic spectra
• Radioactive decay
Obeys Galilean transformation
Introduction
Section 0
• Brownian motion
Lecture 1
Blackbody radiation
Wein’s Law
Photoelectric effect
Diffraction of x rays
Slide 25
•
Existence of Atoms!
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Lecture 1 Slide 25
Then All Hell Broke Lose
“Thirty Years That Shook Physics”
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
1887 Michelson-Morley exp. debunks “ether”
1895 Rontgen discovers x rays
1897 Becquerel discovers radioactivity
1897 Thomson discovers the electron
1900 Planck proposes energy quantization
1905 Einstein proposes special relativity
1915 Einstein proposes general relativity
1911 Rutherford discovers the nucleus
1911 Braggs and von Laue use x rays to determine crystal structures
1911 Ones finds superconductors
1913 Bohr uses QM to explain hydrogen spectrum
1923 Compton demonstrates particle nature of light
1923 de Broglie proposes matter waves
1925 Davisson & Germer prove matter is wavelike
1925 Heisenberg states uncertainty principle
1926 Schrodinger
develops
wave equation
Introduction Section
0 Lecture
1 Slide 26
1924-6 Boson and Fermion distributions developed
•
1949 Murphy's Law stated
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Lecture 1 Slide 26
Current State of Physics cira 2009
Conservation Laws
Statistical Mechanics
•
•
•
Electricity & Magnetism •
• Physics of many particles
• Fermions and Bosons
• Partitioning of Energy
• Thermodynamics
• Time and Entropy
Energy
Linear & Angular Momentum
Charge, Spin
Lepton and Baryon Number
Maxwell Equations (c 1880)
Weinburg-Salom Model
• QED
• Unites E&M, Weak NF
Mechanics (Gravity)……
Weak Nuclear Force
General Relativity
Space and time
Radioactivity
Standard Model
Quantum Mechanics
Introduction
Section 0
•Schrodinger/Dirac
Equation
•Probabilistic approach
Lecture 1
Slide 27
• QCD
• Unites E&M, Strong NF, Weak NF
Strong Nuclear Force
INTRODUCTION TO Modern Physics PHYX 2710
Composition of subatomic particles
Fall 2004
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INTRODUCTION
Lecture 1 Slide 27
Limits of Current Modern Physics
Dimension Range of
Applicability
Range of Application
Length
10-18 to 10+26 m
Quark size to the universe size
Mass
10-31 to 10+40 kg
Electrons to galactic clusters
Time
10+3 to 10+22 sec-1
10-16 to 10+17 sec
Radio to Gamma rays
Sub-femtosecond
spectroscopy to age of
universe
Velocity
10-8 to 10+8 m/s
Introduction
Section 0
Lecture 1
Slide 28
Sub-atomic particles to speed
of light
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 28
Inconsistencies in Physics cira 2009
Statistical Mechanics
• Fermions,
Bosons and Anyons
•Bose-Einstein Condensates
•Superconductivity
•Stellar Evolution
• SM of Black Holes
• Time and Entropy
Conservation Laws
•
•
•
Electricity & Magnetism •
Maxwell Equations (c1880)
Energy
Linear & Angular Momentum
Charge, Spin
Lepton and Baryon Number
Heavy Fermions and HTSC
Chaotic and complex systems
Gravity………………
•
•
•
•
•
General Relativity
Space and time
Inconsistent with QM
Search for dark matter
Fixed gravitational constant?
Weak Nuclear Force
• Radioactivity
• CPT violations?
GUT’s and TOE’s
Quantum Mechanics
Section 0 Lecture 1 Slide 29
• Existence ofIntroduction
atoms
Strong Nuclear Force
•Schrodinger/Dirac Equation
•Composition of subatomic particles
• Sub-atomic particles
•Matter/anitmatter imbalance
• Probabilistic approach
•Decay ratios and particle masses
•Teleportation INTRODUCTION TO Modern Physics PHYX 2710
•Search for Higgs Bosons
Fall 2004
•Entwined states
•Nature of strong hadron force
•Sub-Planck length physics
•Proton decay
Physics of Technology—PHYS 1800
Spring 2009
INTRODUCTION
• Combining Standard model
and Gravity
• String Theory
Lecture 1 Slide 29
Physical Principles and Theories
Physical principles and theories are used to explain
fundamental interactions in:
Life sciences:
Physical sciences:
↓
Living organisms
– Biology
– Zoology
– Health
↓
Physics
Chemistry
Geology
Astronomy
Oceanography
Meteorology (weather)
Physics
is the
most
quantitative
of the sciencies and
Introduction
Section
0 Lecture
1 Slide 30
uses measurements and mathematics to develop
and test its theories.
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 30
How are scientific explanations/laws developed?
1. Careful observations reveal an unknown natural
phenomena…(try to find answers - read books, search web…)
2. Gather facts and measurements about phenomena,
study other people’s ideas and try to develop an
“empirical law” based on your results.
3. Invent a “hypothesis” to explain your observations and
empirical laws.
4. Develop experiments to test your hypothesis. (Controlled
experiments in laboratory preferably.)
Introduction
Section 0
Lecture 1
Slide 31
5. Publish your results in scientific literature. (critical review…)
INTRODUCTION TO Modern Physics PHYX 2710
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Lecture 1 Slide 31
Scientific Method:
Leads to new discoveries → how scientific
progress is made!
Careful measurements,
Experiments
Empirical
laws,
Introduction Section 0
Generalization
Hypothesis,
Lecture 1
Slide 32
Theory
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Fall 2004
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Lecture 1 Slide 32
Role of Mathematics in Physics:
Math is used as a tool in physics helping to make more
concise statements than are possible using words alone.
Math provides an accurate and convenient way of
summarizing a physical law for investigating its properties.
Math is a “universal” language and is not limited by
national, ethnic or social boundaries.
Example: The distance traveled by a truck is equal to its average
speed of motion multiplied by the time the journey
takes.
or
D= S* t
Introduction
Section 0
or
Lecture 1
where D = distance
S = average speed
t = journey time
Slide 33
where
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Σ=ν*τ
Σ = distance
ν = average speed
τ = journey time
Same formula - different symbols
Physics of Technology—PHYS 1800
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INTRODUCTION
Lecture 1 Slide 33
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PHYS 1800
Lecture 1
Principles of Physics
Introduction
Section 0
Lecture 1
Slide 34
An Example of Deductive Reasoning
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Lecture 1 Slide 34
Solving the Mystery
?
Observations:
1. Candles stayed lit until beaker tipped.
2. When apparently empty beaker tipped, the candles
went out one by one, top one first.
Measurements:
Introduction Section 0
Lecture 1
Slide 35
1. Measure time separation between each candle going
out.
2. Lower angle of trough to see if all candles go out or
Lecture 1 Slide 35
not.
INTRODUCTION
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Possible hypotheses:
1. Lights extinguished as colorless water from beaker
flows past each candle one by one.
(Qu: Do you see any water at the bottom of
trough?)
2. Lights extinguished as air tipped out of beaker
rushes past candles one by one.
(Qu: Did you notice flames flicker in wind?)
3. Lights die out due to very cold air rolling out of
beaker.
Introduction Section 0 Lecture 1 Slide 36
(You could measure the temperature of the
beaker; but how could cold air alone put out the
flames?)
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
4. Lights out due to unknown
colorless gasLecture
flowing
1 Slide 36
INTRODUCTION
Physics of Technology—PHYS 1800
Spring 2009
Final Hypothesis:
A cold , heavy, colorless gas that does not
burn flowed out of the beaker and
extinguished the flames one by one as it
displaced the air that is rich in oxygen
around them.
Answer = Carbon Dioxide (CO2)
Introduction
Section 0
Lecture 1
Slide 37
(“Dry ice” freezes at -78.5° C or -109° F)
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Lecture 1 Slide 37
Physics of Technology
Next Recitation:
Math and Problem Solving Review
Tuesday 1:30-2:45
ESLC 53
Review Appendices A,B,C
Next Class:
Introduction
Section 0
Lecture 1
Wed
Slide 38 10:30-11:20
BUS 318 room.
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INTRODUCTION
Lecture 1 Slide 38