Transcript Scientific Measurements

Chapter 1 - About Science
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Scientific Measurements
Scientific Method
Scientific Attitude
Science, Art, and Religion
Science and Technology
Physics, THE Basic Science
In Perspective
Physics 1100 – Spring 2012
Scientific Measurements
• Hallmark of a good science
• How far back has man been making “scientific measurements”
– Seasons
– Sizes
– Distances
• Measurements and observations not only allow us to describe, but
to predict!
– How high will a ball bounce?
– What are the rules of the “game”
Physics 1100 – Spring 2012
An Historical Example - The size of the Earth
Eratosthenes ~235 BC
(Egypt - noon June 22)
1/50 of a circle & distance is 800Km
Physics 1100 – Spring 2012
The size of the Moon
Aristarchus ~ 240 BC
12,740/3.5 = 3,640Km
Physics 1100 – Spring 2012
Distance to the Moon
(the early Greeks knew this!)
Physics 1100 – Spring 2012
What Is Science?
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Which of the following best describes “science”?
– A compendium of answers
– A set of rules about the natural world
– A methodology
– Exploration, curiosity; a compendium of questions
– Observation, experimentation
Science has bits of all these (esp. last four)
Physics 1100 – Spring 2012
Science is Verifiable by Others
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Embrace Ideas that can be tested
Science tends to be self-correcting
Hypothesis, Theory, Laws, Fact,
Testable Predictions
“No number of experiments can prove me right; a single
experiment can prove me wrong” – A. Einstein
Physics 1100 – Spring 2012
Science = A Process for Change!
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Discovery
Experiment/Observation
Hypothesis
Prediction
Test
Theory
An ongoing cycle – the “scientific method”
Physics 1100 – Spring 2012
What is “Physics”
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An attempt to rationalize the observed Universe in terms of
irreducible basic constituents, interacting via basic forces.
– Always look for the simplest explanation
An evolving set of (sometimes contradictory!) organizing principles,
theories, that are subjected to experimental tests.
This has been going on for a long time.... with considerable success
Physics 1100 – Spring 2012
Physicists View of the World of Science
Engineering
Biology
Geology
Chemistry
Astronomy
Physical
Reality
Abstraction
Our
Universe
Physics 1100 – Spring 2012
Physics Goals
• Attempt to find unifying principles and properties e.g.,
gravitation:
Kepler’s laws of
planetary motion
Falling apples
Universal
Gravitation
“Unification” of forces
Physics 1100 – Spring 2012
Physics Goals
All the stuff you see around you
Chemical compounds
Elements (Atoms)
e,n,p
Superstrings?
Many thousands
Many hundreds
Tens
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An ongoing attempt to
deduce the basic building
blocks
Physics 1100 – Spring 2012
An Evolving World View
• As our understanding grows, theories are supplanted (or
subsumed)
Kepler’s laws of
planetary motion
Falling apples
General
Relativity
Universal
Gravitation
Physics 1100 – Spring 2012
Clicker Questions
1) The scientific method is most effective in
A) gaining, organizing, and applying new knowledge.
B) making theories.
C) performing experiments.
D) discovering new things.
E) making hypotheses.
2) In science, an educated guess is a
A) theory.
B) hypothesis.
C) both of these
Physics 1100 – Spring 2012
Clicker Questions
3) In science, facts
A) mean very little.
C) may change.
B) are absolute.
D) are more important than theories.
4) The synthesis of a large collection of information that contains
well-tested and verified hypotheses about certain aspects of the
world is known as a scientific
A) hypothesis.
B) law or principle.
C) theory.
D) fact.
E) none of these
Physics 1100 – Spring 2012
Clicker Questions
5) Which of the following is a scientific statement?
A) The moon is made of green cheese.
B) There are parts of the universe that will never be found by man.
C) Matter is filled with undetectable particles.
D) There are things we will never know about.
E) none of these
6) The statement, "There are regions beneath the Earth's crust that
will always be beyond the reach of scientific investigation," is a
A) fact.
B) scientific statement.
C) speculation.
D) theory.
E) hypothesis.
Physics 1100 – Spring 2012