TEACHING INTRODUCTORY PHYSICS, CONSERVATION
LAWS FIRST:  CONFERENCE SUMMARY

Table of contents:

1.) ERIC AND CATHERINE: OPENING REMARKS (back)

Purpose is to develop a list of helpful information for the group.
*What are the major student difficulties in learning?
*What are the goals of teaching physics? Remember that only 1 in 33 of freshman physics students becomes a physicist.
*Look at applications of physics to other disciplines, e.g. fluid dynamics in circulatory system.
*Remember the importance of the grade and the frustration of students in introductory courses.
*Keep in mind the question of content as process. My goal is to teach a way of thinking about problems, analysis and application rather than memorization.
*One goal of teaching- John Toll- is to chase away superstition.

2.) GLOVER (TEXAS A&M) AND RICHARDS (ROSE-HULMAN): CONSERVATION LAW-BASED CURRICULUM: AN ENGINEERING PERSPECTIVE (back)

They see engineering as a unified and coherent body of knowledge – applies to multidisciplinary problems. Generation and consumption of P (momentum) and E (energy) are fundamental.
Richards feels physics provides a framework for engineering, to the students. He also emphasized systems. It's important to remember that engineering problems generally deal with open rather than closed systems. Moreover, information is often incomplete. One must make estimates and reasonable assumptions.
Physics problems at the elementary level nearly always treat closed systems, and give complete information (and no extra information).

3.) DISCUSSION OF LABORATORIES (back)

We agree that we want effective labs:
a.) What qualities make a laboratory effective?
b.) What is purpose of a laboratory in an introductory physics course?

One can divide labs into the recipe type and the research type. It is certainly difficult to do a research lab at the introductory level. It could be done were each concept introduced through a laboratory without benefit of a textbook. This would require an increase of time and certainly more instructors.

Goals of laboratories should be to:
* develop students' intuition and
* force them to confront misconceptions (e.g. heavier bodies fall faster).

Labs should, when possible, connect physics and students' knowledge. Too often students believe that laboratories and the course have no relation to the "real world".

Two labs mentioned:
1.) Acoustics and music – frequency analysis of waves.
2.) Measure temperature of ice using a false thermometer - set at 38 degrees.

Problems of measurement, error, equipment that malfunctions: Some recipe labs are good in that they are learning tools (like traditional problems).

4.) DAVID GOODSTEIN: THE BIG CRUNCH (back)

Until 1970, there was linear growth in the enterprise of science. In 1970, both the left and the right turned against science. Foreign students and post-docs took up the slack. Today the cold war is over. The age of academic expansion is over. Today, physics is, in many ways, a service industry.
During a period of exponential growth, institutions had self-interest in process. Now, due to diminished concentration of resources, peer review of proposals leads to intrinsic conflict of interest. The research university is in many ways an entrepreneur. They want professors to repay the investment.

Questions:

i.) Can science survive the constraints?
*No guarantee in the marketplace.
*Government, according to Lederman, is starving science.
*Less funding because of the end of the Cold War.
*Aged leaders: they came of age during the "Golden Age".

ii.) Is science finished? What does science do?
*Horgan – science poses questions and answers them.
*Michelson – it measures the 6th decimal place.
*Feynman – it extracts the simple from the complex.

There is a paradox in our attitudes today. 1 in 33 of first year physics students will become physicists. We favor the elite and look down on the illiterate. We carry out educational "mining and sorting" and throw away the non-elite.

iii.) Why study physics?
We have a body of knowledge in physics. Our responsibility is to pass on this knowledge. Also we chase away superstition. There is a need for physics in many professions. We have a responsibility these professions. As one person said, he would like physics to be an essential subject for anyone who considers himself to be educated.

5.) PARTICIPANT PRESENTATIONS (back)

Fundamental ideas in E and M theory are:
*Fields
*Symmetry
*Modeling

We should apply these to Maxwell's Equation as we study them. Try to develop these fundamental ideas as we examine the equations, rather than deal with the equations as though they were the equivalent of Euclid's axioms. Use geometric models to clarify the differences between sources of E (with vector) and sources of B (with vector).

Texas A & M has coordinated the teaching of calculus and physics. To do so requires presenting topics in a somewhat nontraditional order in both calculus and physics. It requires that the two departments talk regularly. I should speak to the math department at Rivers and see if we might not coordinate our courses to improve both math and science teaching.

She uses project-oriented labs for a general physics/calculus based course. She criticized traditional lab and concept labs. The traditional lab is set up to verify a law already known, the students are bored. There is no real examination of concepts. In many ways, it is just busy work.

Concept labs are still boring. They are also passive. Her goals:
*Develop problem solving skills
*Relate to real world
*Work on concepts
*Do science
*Use equipment
*Use shop

Her long term projects (honors GP):
*Each group does 1 experiment
*Continual appraisal
*Progress report
*Final report

Her short term project:
*Challenge - no report - single period

For regular group:
* 3 4-week blocks
*6 different labs in each section

Each lab presented as challenge- 4 parts:
a.) Introduction to equipment - practical
b.) Planning - develop procedure
c.) Do experiment
d.) Presentation

At MIT, one introductory physics sequence developed and taught by John King, Philip and Phyllis Morrison, Tony French, and Peter is built around a series of take-home experiments. Any given experiment is used to illustrate many different concepts (for example, the first experiment of the semester involves measuring the viscosity of water; at first it is used simply to illustrate the nature of data, and then later it is used to discuss conservation laws and fluid mechanics). The experiments must be inexpensive (so that every student can have a kit), possible to do at home, and take a reasonable amount of time. A "culture" of older students helping younger students in the dormitories has grown up around this course and these labs. Peter is giving all of us kits to try "Experiment Flow" on our own and we’ll see how we instructors do.

6.) CATHERINE CROUCH: PEER INSTRUCTION (back)

Peer instruction is a form of collaborative learning. It turns a lecture into a seminar. In problem solving, one must choose between algorithms and concepts. Algorithms lead to memorization. The solution is to have students explain the concepts in class.

Procedure:
a.) Students should do reading before class. This is a challenge. How to get students to read is a constant question (in universities as in schools).
b.) The instructor lectures for about 10 minutes then gives a ConcepTest – multiple-choice with 3 or 4 possible answers.
c.) Each student thinks about the question and answers individually.
d.) They form groups of 2 or 3 students – discuss answers and revise their initial answers if necessary (try to come to group consensus).
e.) Explanation by instructor.

For a "good" question, 35 - 65% will get the right answer the first time. Students do get involved.

Reading incentives:
*Quizzes
*Summaries
*Memos - questions on reading

Choosing Good Questions:
a.) Key concept
b.) Real life situations
c.) Identify student difficulties (attractive wrong answers)
d.) http://galileo.harvard.edu

*Try to have follow-up problems for after class.
How do we determine if understanding accompanies reading?
-Try to have students produce summaries without equations. Can they write clearly about the principles?

7.) PARTICIPANT PRESENTATION: (back)

Dany Kim-Shapiro and Peter Saeta both use web-based assignments to get students to read before class and in the process gain information right before class on what their students do and don’t understand. Peter notes that learning to read requires practice.

8.) DISCUSSION: COLLABORATIVE LEARNING IN LECTURES (back)

Linda Jones: Didn't lecture in quantum mechanics. Used tutorials and problem solving sessions. When she lectured (half period) in response to student pressure/requests she wasn't so effective.

Kubinec: Instructor's role in collaborative learning is crucial: must buy into it wholeheartedly and must motivate the students to participate. In high school, students just sat in class and were passive receptacles. Kubinec has used peer instruction in class.

Gatland: He is a resident skeptic. He has 1000 student course and 6 instructors. He wants a package of texts and exercises. Wants to know what can be done within traditional framework? It should be easy to implement.

Suggestion: 10-minute mini-lecture and 10 minute peer lecture.

*For me to try: ask students to prepare 10-minute lecture for class from time to time. I'd grade it. (Can't ask for anything without grading it.)

Birkett: Purpose of reading is to provide terminology and definitions. Give a problem in class 3/4 minute. Remember that exams drive student behavior. Think about group or pair exams. How does one build group functioning? Can one develop a non-competitive atmosphere? Instructor must be willing to give up control. Need for students to read in advance.

Role of Instructor:
a.) provide motivation
b.) identify conceptual pitfalls and follow up to see if they are corrected
c.) demonstrations

9.) JOHN HIRSHFELD: PHYSICS AS PREPARATION FOR MEDICINE (back)

Why is physics important to medicine?
a.) Physics explains how the body works.
b.) Teaches an approach to problem solving.

What is the core of knowledge needed by a physician?
a.) Bioscientific basis of disease
b.) Clinical practice: diagnosis/management/therapeutics
c.) Medical decision making based on evidence: understanding of hypothesis testing.
d.) Epidemiological approach
e.) Self-directed learning

Problem Solving:
a.) Information gathering and analysis
b.) Note that MD's often have incomplete information plus limited time frame to make a decision in a high stakes situation.
c.) Must tolerate ambiguous situations

*Important for teaching: We usually give complete information, and do not give superfluous information. We do not require them to determine what is relevant and what is not

The Socratic method is used extensively in medical education (especially the clinical stages). Students are rarely comfortable with it prior to arriving at medical school, however; if they are exposed to it as undergraduates they have an advantage.

Medicine requires knowledge of physics:

Newton's Laws
Work and energy
Fluid static's and dynamics
Law of LaPlace / Reynolds Number
Oscillations: Waves and Sounds
Electricity and Magnetism
Electromagnetic Radiation
Radioactivity

Physical Chemistry:
Gas laws
Osmotic pressure
Electrochemistry
Molecular changes/polarity/interactions between molecules

Discussed cardiovascular system as problem in fluid dynamics: applications of Bernoulli’s equation, Reynolds number, Poiseuille’s equation. Heart murmurs: audible result of turbulent rather than laminar flow through heart valves.

T = Pr/2 Law of LaPlace applied to spherical or quasi-spherical fluid-filled cavities

(T = surface tension in wall of vessel

P = pressure in cavity

r = cavity radius)

*For Phys E1, look at question on MCATs.

10.) DEBORAH HUGHES HALLETT: LESSONS FROM THE CALCULUS REFORM MOVEMENT (back)

Issues in teaching of calculus – must learn what students think! Great concern about student performance. Math is keeping students out of science. Problems have started in high school. College students arrive without fluency in high school math and feel a lack of confidence. We must examine the effect of technology (i.e. calculators) on teaching?

CONCEPTS VS "GETTING ANSWERS"

Many kids look on math as a procedure. They find that puzzling things out is "scary". We must recognize that procedure alone is not enough. It is impossible to think hard while covering too many topics. Deborah stressed reducing the number of topics. She also pointed out that in grade school, one keeps revisiting topics. In contrast, high school offers a single shot and then goes on.

Note that math uses few numbers, and they're clear. e.g. In quadratic equations math uses 5x2 - 2x + 3 = 0.
In contrast, physics must have 22.46 t2/s2 - 170.9 t/s + 33.42 = 0.
Students who can solve the first are often lost with the second. Physics deals with "messy" numbers and units.

Both high school and college students have an enormous deficiency in quantitative graphical reasoning. They cannot go from graphs to equations and the reverse. Also, much confusion with symbols beyond x and y.
She feels we must use technology to make people think about math. Intuitive learning is fine but it must lead to rigorous understanding.

11.) DUDLEY HERSCHBACH: PHYSICS AS PREPARATION FOR CHEMISTS (back)

Beginning students have a fear of physics. Yet there is a great need for physics in chemistry. In his course, he has a chat site for students to ask questions and receive answers.

Topics:
*Gas laws
*Water Pump - physiology of a giraffe. How can he drink?
*Use of gas laws to teach ratios.
Large numbers (e.g. weight of the earth's atmosphere).
*Importance of language.
Science requires language.
*Energy
Thermodynamics/free energy

12.) WILL ANDREWES: MEASUREMENT TECHNOLOGY (back)

Harrison and Longitude Problem

13.) WOLFGANG RUECKNER – LECTURE DEMONSTRATIONS (back)

a.) Bicycle/spool (torque)
b.) Which ball reaches the end first on two different tracks?
c.) Standing waves in tube half-filled with kerosene
d.) Mixing and unmixing dye in high viscosity fluid (glycerin?)
e.)

14.) ERIC - CHAPTERS 7,8 (back)

Galilean relativity - conceptual difficulties originate in Galilean relativity. Avoid accelerated reference frames at start. Use Newton’s 1st law to define inertial frames. Remember that a change in kinetic energy (K) is frame-dependent, while overall energy conservation is frame-independent. Also worry about total kinetic energy of composite objects:

K_tot = (M v_cm²)/2 + K_{relative to cm}

Interactions:
Even in elastic collision K is not conserved during collision. An elastic collision is an inelastic collision succeeded by a reversed inelastic collision. Points out that gravitational potential energy (U_grav) of an isolated body is meaningless if the earth is not included in the system.

Change in configuration of system ==> Change in U.

Discussed:
Source Energy
Mechanical Energy
Dissipation Energy
Discussion of order/disorder and reversibility: can’t convert all mechanical energy back into source energy.

15.) GAY STEWART: INCORPORATING EFFECTIVE GROUP DYNAMICS INTO PHYSICS EDUCATION MATERIALS. (back)

Gay has looked at differences between the written work of students in her section of E & M and students in a more traditionally taught section. Students in her class use more words on their homework, use more algebraic symbols (and substitute numbers in nearer the end of their process), order their solutions more neatly and logically, and generally do more homework. Since one of her goals is for her students to learn to solve problems well, she seems to be succeeding!

16.) ERIC: CHAPTERS 9 AND 10 (back)

Force = dp/dt
Discussed free body diagrams.
Notation
Ftype BO=BY ON
BO

Work: defined to be change in total energy of a system due to the action of an external force.

Force can cause ? K, ? U, ? E_diss.

17.) PHIL SADLER: DOES HIGH SCHOOL PHYSICS HELP? (back)

Why students have difficulties in college physics:
a.) Poor preparation in high school
b.) Poor teaching at college level

Most students who took physics in high school take it at college level. However, many more high school students take biology than they do physics.
Sadler has examined what factors are correlated with success in college physics.

Most significant correlation: student’s socioeconomic status.

Certain qualities of high school courses are also positively correlated with grade in college (though much less than socioeconomic factors). They include:
a.) Rigorous quantitative courses (not just qualitative)
b.) Reduced coverage: emphasize fundamental concepts and mastery/root out misconceptions
c.) Solve problems in many ways, don't just give algorithms

He found that the text, laboratories, and even homework (if it were just blind substitution) made little difference.
Discussed MIT/Harvard quiz (can you light a bulb with battery and a single wire?)
To teach and test students effectively, one needs to know misconceptions of students.

Summary:
a.) Less is more
b.) Be quantitative

Note to RN:
Try a test with different answers. Have students choose one and prove which is correct. Show why wrong answers are wrong.

18.) KEN AND PATRICIA HELLER: COOPERATIVE GROUP PROBLEM SOLVING: STRATEGIES FOR SUCCESS (back)

Goals of problem solving (P.S.)
Why?
What?
Teaching P.S.
Designing problems
"context rich" problems

Students must learn: Concepts
Vocabulary
Quantitative Techniques
Go beyond memorization.

Teach students how to approach P.S:
a.) General principles
b.) Plan
c.) Procedures: "chunking" reduce problems to manageable parts.
d.) Review progress – be self-critical.

In writing problems do not provide pictures – students need to learn to interpret problems into drawings. They must learn to plan solutions. Too often, students begin writing things down at random, in hope that something will work. After planning, they should outline steps for the math solution. Finally, be sure to keep units in all steps and check them at the end.

In writing "context rich" problems begin with "you". Try to connect problems to real situations. When possible write them in terms of strategies - what should you do to have (or avoid) something happen? Students should make and list assumptions.

For labs - ask for predictions.
Be sure to set class goals.

19.) DISCUSSION ON SMALL GROUP WORK (back)

Hand out problems to group. They then discuss the problem as a group, but solve them individually. Many ways to grade:
a.) individual grades
b.) one grade for group – highest average, or lowest (lowest puts burden on explaining)

Homework groups. Set up homework teams. As an incentive, include a homework problem on a test.
Some feel that a group project with hands-on work is more effective than group problem solving.
Use teams of 3 or 4 students. Never 2 males with 1 female. Important to teach teamwork skills and to facilitate.

20.) McDERMOTT: TUTORIALS IN INTRODUCTORY PHYSICS (back)

See her books. Goal is to bridge the gap between teaching and learning.
Books (Wiley) Physics By Inquiry improves student learning in introductory physics
Typical student sees physics as collection of facts and formulas. They do not see the role of reason. Many can't apply what they've learned.

Need to develop ability to:
*reason
*apply
*and understand

Need for students to be intellectually active. Tutorials supplement instruction.
*construct concepts
*develop reasoning
*apply to real world

Her exams include questions from the tutorials. (Ex: Problem with Atwood's machine)
Qualitative understanding must come before formalism (quantitative).
Force the student to go through reasoning.

21) ERIC: CHAPTERS 11,12 (back)

Pointed out that static friction differs from kinetic friction: static friction does not dissipate energy.
Note: Frictional and normal forces are two components of a single contact force.