Date post: | 28-Dec-2015 |
Category: |
Documents |
Upload: | hilda-gray |
View: | 222 times |
Download: | 2 times |
Thomas A. MooreIntroductory Calculus-Based Physics Conference
November 1, 2003
Six Ideas That Shaped Physics:
An Overview
A textbook, instructor’s manual, and website
A new approach to teaching introductory physics based on four fundamental principles:
1. New approaches can provide increased insight
2. Active learning solidifies understanding
3. Explicit instruction and practice with model-building provides flexibility
4. Contemporary physics provides excitement
What is Six Ideas That Shaped Physics?
To describe the structure and goals of a Six Ideas course
To discuss how the Six Ideas materials express the four principles mentioned
To present evidence that the approach works
My goals in this presentation
NSF-funded project (1987-1995) whose purpose was to develop and test alternatives to the standard course
Summative report: Am. J. Phys. 66, pp. 124-137 (February, 1998)
Principles articulated by the IUPP committee:
1. Less is more
2. Include 20th century physics
3. Use a storyline
The Introductory University Physics Project (IUPP)
The text is divided into six volumes, each focused on a single formative idea
1. Unit C: Interactions are Constrained by Conservation Laws
2. Unit N: The Laws of Physics are Universal
3. Unit R: The Laws of Physics are Frame-Independent
4. Unit E: Electric and Magnetic Fields are Unified
5. Unit Q: Matter Behaves Like Waves
6. Unit T: Some Processes are Irreversible
The structure of Six Ideas
Each idea provides a “story line” for the unit
They also motivate necessary cuts
Some large-scale cuts (geometric optics, fluids)
Mostly, the pace is cut by streamlining
The “chapter per day” format defines the pace
Contemporary physicsUnits on relativity and quantum physics
Contemporary perspective throughout
How this structure addresses the IUPP goals
Common student problems
Identifying forces linked by Newton’s 3rd law
Identifying fictitious forces
These problems are related
Students see forces as isolated entities that are not linked to any deeper conceptual structure
Standard presentations reinforce this
How new approaches can improve learning: an example
In Six Ideas, the interaction between two objects (not force) is the fundamental concept
How this addresses the problem
The forces that are linked by Newton’s 3rd law are always the two ends of a specific interaction
Fictitious forces do not reflect an interaction
How new approaches can improve learning: an example
Other payoffs for this approach:
Helps make the concept of potential energy clearer
Helps students better understand the similarities between force, power, and torque
Momentum-flow images help students qualitatively predict motion without calculus
How new approaches can improve learning: an example
The most robust result of physics educational research: Students learn by doing
We all know this, but our courses are not usually structured as if this were true
Six Ideas supports active learning in four ways:1. Support for reducing the need for lectures2. Support for activities during class3. Support for active learning outside of class4. Support for intelligent course design
Support for Active Learning
Text is written more like a conversation, less like an encyclopedia
Helps for active reading
Wide margins for student notes
In-chapter exercises help challenge students to think about what they are reading (and answers in the back provide instant feedback)
Overview/summary at the beginning of each chapter displays the big picture
Support for Reducing Lectures
Support for class activities
“Two-minute” problems
Active demonstrations
N2T.9 A car moving at a constant speed travels past a valley in the road, as shown below. Which of the arrows shown most closely approximates the direction of the car’s acceleration at the instant that it is at the position shown? (Hint: draw a motion diagram.)
A B C D E F T
zero
A B C D E F T
zero
“Rich-Context” problems support collabo-rative work in active recitation sections
Generally, problems cannot be solved by “plugging and chugging”
Active learning outside of class
C7R.2 You are prospecting for rare metals on a spherical asteroid composed mostly of iron (density ≈ 7800 kg/m3) and whose radius is 4.5 km. You’ve left your spaceship in a circular parking orbit 400 m above the asteroid's surface and gone down to the surface. However, one of your exploratory explosions knocks you against a rock, ruining your jet pack. (This is why you have a backup jet pack, which is, unfortunately, “back up” in the spaceship.) Is it possible for you to simply jump high enough to get back to the spaceship?
To be successful, course design must
Motivate students to read text before class
Help them focus on ideas instead of formulas
Encourage them to learn from difficult problems (instead of freaking out)
Details are important!
The instructor’s manual (available online) offers ideas about how to do this well
Support for good course design
Real applications always involve discerning a simple model in a complex situation
Building a model involves self-consciously making approximations and assumptions
Learning to do this well is an art that students learn by both instruction and practice
Instruction in Model-BuildingWhy is this important?
The text extensively discusses how to build models and make appropriate approximations
It teaches and uses a four-part problem-solving outline: Translate, Model, Solve, Evaluate
It explicitly teaches the value of tools such as unit analysis, symbolic algebra, the method of extremes, estimation
It extensively uses diagrams as thinking tools
Computer models help students explore consequences of physical models
Instruction in Model-Building
Why teach relativity and quantum physics?
Well, this is the 21st century…
32/33 will never take another physics course
One of the clearest signals from IUPP evaluation was the interest in these topics
Six Ideas uses contemporary ideas throughout
It addresses how topics fit into current physics
It explores contemporary applications
Its problems have a very practical orientation
Contemporary Physics
The FCI Exam (Physics Teacher, 30, 3, 1992)(a difficult but purely conceptual multiple-choice exam on Newtonian physics)
R. Hake, Am. J. Phys. 66(1) (January 1998)
The normalized gain g = (post - pre)/(100% - pre)] is a robust measure of course performance
Traditional courses: g = 0.23 ± 0.04
“Interactive engagment” (IE) courses: g = 0.48 ± 0.14
Not correlated with instructor, initial student state
Does Six Ideas work?
Results from Pomona College
1993: 0.46
1996: 0.48
1997: 0.45
1998: 0.55 (estimated)
2000: 0.63
2001: 0.58
Does Six Ideas Work?
Vic DeCarlo at DePauw University2000: 0.542001: 0.55
Ulrich Heinz at Ohio State (Columbus)2001: 0.72 (!)
Note that Six Ideas spends less time on mechanics than most IE courses
Good gains seem to happen even if the classes are not especially interactive
Does Six Ideas Work?
Six Ideas provides (without requiring costly staffing, scheduling, or infrastructure changes)
A contemporary and effective approach to physics
Support for active learning
Explicit instruction in model-building skills
It has been classroom-tested for > 10 years
It provides extensive support for instructors
For more: www.physics.pomona.edu/sixideas
Conclusions