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Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Conceptual Physics
Fundamentals
Chapter 1:
ABOUT SCIENCE
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
This lecture will help you
understand:
• Science
• Mathematics—The Language of Science
• Scientific Measurements
• Scientific Methods
• The Scientific Attitude
• Science, Art, and Religion
• Science and Technology
• Physics—The Basic Science
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Science
Science
• is a body of knowledge
• is an ongoing human activity
• has beginnings that precede recorded history
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Astronomy
•1500 BC- Stonehenge used to track the sun and mark the solstice
•1200 BC- Babylonians study 'astrology' & invent the 12 signs used today
•280 BC- Aristarchus (Greek) stated that the Sun was the center of the 'solar
system'. It was almost 1800 yrs later that his theory would be widely accepted.
Early man studied the moon & the sun to learn when to sow their crops and when
to harvest. We still use this method to this day.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Invention of the Wheel
• It is still a mystery as to who invented the wheel and
when the wheel was invented.
• According to archaeologists, it was probably invented
in around 8,000 B.C. in Asia.
• The oldest wheel known however, was discovered in
Mesopotamia and probably dates back to 3,500 B.C.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Science
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Mathematics—The Language of Science
Integration of science and mathematics
• occurred some four centuries ago
• ideas of science are unambiguous when
expressed in mathematical terms
• equations of science provide expressions of
relationships between concepts
• equations are “guides to thinking”
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Early Mathematics
• 1800 BC – Babylonian clay
tablets cover topics which
include fractions, algebra,
quadratic and cubic
equation
• Babylonian mathematics
were written using a base-
60 numeral system. This
derives the modern day
usage of 60 seconds in a
minute, 60 minutes in an
hour, and 360 (60 x 6)
degrees in a circle.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Algebra
• The word algebra is a Latin variant of the Arabic
word al-jabr. This came from the title of a book,
Hidab al-jabr wal-muqubala, written in Baghdad
about 825 A.D. by the Arab mathematician
Mohamad ibn-Musa al-Khowarizmi
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Mathematics as Mechanized Thinking
• Use mathematics to change scientific statements. If the original
statement is correct, and you follow the rules faithfully, your final
statement will also be correct.
This is a new statement about nature - derived using the rules of
mathematics. Using mathematics, physicists can discover new
relationships among physical quantities - mathematics mechanizes
thinking.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Scientific Measurements
Measurements
• relate to how much you know
about something
• of pinhole images of the Sun
nicely lead to a calculation
of the Sun’s diameter
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Measurement
• Measurement is one of the first intellectual
achievements of early humans.
• People learned to measure before they
learned how to write and it was through
measurement that people learned to
count.
• Since humans have ten fingers, we
learned to count by tens
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Early Measurement Units
• inch - the width of the thumb.
• digit - the width of the middle finger (about 3/4 inch)
• palm - the width of four fingers (about 3 inches)
• span - the distance covered by the spread hand (about 9 inches)
• foot - the length of the foot. Later expressed as the length of 36 -
barleycorns taken from the middle of the ear (about 12 inches).
• cubit - distance from the elbow to the tip of the middle finger (about
18 inches).
• yard - distance from the center of the body to the fingertips of the
outstretched arm (about 36
• inches).
• fathom - distance spanned by the outstretched arms (about 72
inches).
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Scientific Methods
Scientific Methods
• There’s no one method in which scientists do
their work.
• Common steps of most methods:
1. observe
2. question
3. predict
4. test predictions
5. draw a conclusion
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
The Scientific Attitude
The scientific attitude is one of
• inquiry
• experimentation
• willingness to admit error
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
The Scientific Attitude
Scientists
• are experts at changing their minds
• must accept experimental findings
– test for erroneous beliefs
– understand objections and positions of
antagonists
– Subject work to peer reviews
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
The Scientific Attitude Fact
a close agreement by observers about the same
phenomenon
Hypothesis
• an educated guess presumed to be factual until
supported by experiment
• scientific if there is a test to prove it wrong
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Which of these is a scientific hypothesis?
A. The Moon is made of green cheese.
B. Atomic nuclei are the smallest particles in nature.
C. A magnet will pick up a copper penny.
D. Cosmic rays cannot penetrate the thickness of your Conceptual
Physics Fundamentals textbook.
The Scientific Attitude
CHECK YOUR NEIGHBOR
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Which of these is a scientific hypothesis?
A. The Moon is made of green cheese.
B. Atomic nuclei are the smallest particles in nature.
C. A magnet will pick up a copper penny.
D. Cosmic rays cannot penetrate the thickness of your Conceptual Physics
Fundamentals textbook.
Explanation:
All are scientific hypotheses! All choices not only have tests for proving
wrongness, but have been proved wrong. Nevertheless, they still pass the test of
being a scientific hypothesis.
The Scientific Attitude
CHECK YOUR ANSWER
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Which of these is not a scientific hypothesis?
A. Protons carry an electric charge.
B. Undetectable particles are some of nature’s secrets.
C. Charged particles will bend when moving in a magnetic field.
D. All of the above are scientific hypotheses.
The Scientific Attitude
CHECK YOUR NEIGHBOR
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Which of these is not a scientific hypothesis?
A. Protons carry an electric charge.
B. Undetectable particles are some of nature’s secrets.
C. Charged particles will bend when moving in a magnetic field.
D. All of the above are scientific hypotheses.
Explanation:
If protons didn’t carry electric charge, they wouldn’t be deflected when crossing a
magnetic field. This would be a test for showing the hypothesis wrong. So both A
and C are capable of being proved wrong, which makes them scientific. Statement
B, however, has no test for wrongness. It is reasonable speculation—but not a
scientific hypothesis.
The Scientific Attitude
CHECK YOUR ANSWER
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
The Scientific Attitude
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
The Scientific Attitude
Law or principle
• a hypothesis that has been tested repeatedly
and has not been contradicted
Theory
• a synthesis of a large body of information that
encompasses well-tested and verified
hypotheses about certain aspects of the natural
world
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Which of these often changes over time with further study?
A. Facts
B. Theories
C. Both of the above
D. Neither of the above
The Scientific Attitude
CHECK YOUR NEIGHBOR
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Which of these often changes over time with further study?
A. Facts
B. Theories
C. Both of the above
D. Neither of the above
Explanation:
Both can change. Is this a weakness or strength of science? For example, if
everything a child holds true is unchanged when that child grows up, with years of
study, even receiving advanced degrees, then either nothing was learned or the
child was unusually gifted from the start—or was part of a closed system. As we
learn new information, we refine our ideas. Likewise with the fields of science.
The Scientific Attitude
CHECK YOUR ANSWER
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
A person who says, “that’s only a theory” likely doesn’t
know that a scientific theory is a
A. guess.
B. number of facts.
C. hypothesis of sorts.
D. vast synthesis of well-tested hypotheses and facts.
The Scientific Attitude
CHECK YOUR NEIGHBOR
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
A person who says, “that’s only a theory” likely doesn’t
know that a scientific theory is a
A. guess.
B. number of facts.
C. hypothesis of sorts.
D. vast synthesis of well-tested hypotheses and facts.
Explanation:
Theory in everyday speech is vastly different than its use in science. A vast and
verifiable body of knowledge isn’t only a theory; if it passes all its tests, it is
elevated to that status! Newton’s theory of gravity and Einstein’s theory of
relativity, for example, are not idle hypotheses—both are supported by
innumerable experiments. They are more than only theories.
The Scientific Attitude
CHECK YOUR ANSWER
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Science, Art, and Religion
Comparison of science, art, and religion by:
• domain
– science is of natural order and in discovering
and recording natural phenomena
– art is the interpretation and expression of
human experience
– religion involves faith and worship of a
supreme being
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Similarities in Art and in Science
– knowledge of what
is possible in
human experience
and in nature
– knowledge of both
affects our views
and decisions of
the world
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Similarities in Religion and in
Science
– both deal with
unanswered
questions
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Science, Art, and Religion
Leonardo da Vinci draws a hygrometer
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Between a pilot and a priest, who do you think should fly a
commercial jet airplane? Who should perform a marriage?
(Although the questions are no-brainers, they have a point.)
A. The pilot should fly the plane and the priest conduct a marriage.
B. The priest should fly the plane and the pilot conduct a marriage.
C. The pilot should conduct both.
D. The priest should conduct both.
Science, Art, and Religion
CHECK YOUR NEIGHBOR
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Between a pilot and a priest, who do you think should fly a
commercial jet airplane? Who should perform a marriage?
(Although the questions are no-brainers, they have a point.)
A. The pilot should fly the plane and the priest conduct a marriage.
B. The priest should fly the plane and the pilot conduct a marriage.
C. The pilot should conduct both.
D. The priest should conduct both.
Explanation:
The point of the questions is that the pilot and priest have nurtured different skills
for different tasks, and each can do their thing well. Okay, one could argue that a
pilot could adequately do both. But it would be a stretch to say a priest could do
both, unless the priest also had training as a pilot.
Science, Art, and Religion
CHECK YOUR ANSWER
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Science and Technology
• Science is concerned with gathering and
organizing knowledge.
• Technology is the use of scientific
knowledge for practical purposes and to
provide tools for further exploration.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Physics—The Basic Science
• Physical sciences include geology, astronomy,
chemistry, and physics.
• Life sciences include biology, zoology, and
botany.
• Physics underlies all the sciences.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Although physics may be the most difficult science course
in certain schools, when compared with the fields of
chemistry, biology, geology, and astronomy, it is
A. the simplest.
B. still the hardest!
C. the central science, in between chemistry and biology.
D. simple enough, but only for especially intelligent people.
Physics—The Basic Science
CHECK YOUR NEIGHBOR
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley
Although physics may be the most difficult science course
in certain schools, when compared with the fields of
chemistry, biology, geology, and astronomy, it is
A. the simplest.
B. still the hardest!
C. the central science, in between chemistry and biology.
D. simple enough, but only for especially intelligent people.
Explanation:
Just compare the list of terms in the physics chapters of this book with the lists in
chapters of other textbooks. Which lists are shortest? Chemistry, and especially
biology, are enormously more complex than physics. Physics is much more
understood than the other fields—which is why this book begins with physics—a
foundation for chemistry, biology, geology, and astronomy.
Physics—The Basic Science
CHECK YOUR ANSWER