Matter & Interactions: Testing a New Physics Curriculum at

Georgia Tech

Matthew KohlmyerMichael Schatz

Georgia Institute of TechnologySchool of Physics

Intro physics courses at GT

• Traditional curriculum• Many students: 1700 per sem. in Phys. 1 & 2• Large lecture (>200 students) w/ small lab

section (20 students)• Problems:

– GPA significantly lower than other intro courses– 25% D’s or F’s– Unpopular w/ students

• Student newspaper routinely voices criticism

– External review committee criticized structure, outcomes of intro courses

Why change intro physics?

Fails to prepare future scientists & engineers:

– Nanotechnology– Materials science– Quantum computation

Tools needed:– Computer modeling of

complex systems– Skills to solve new

problems

Problems with traditional course:

– Lack of 20th century physics

– Macroscopic (no atoms!)– No computer modeling– Emphasis on “Equation

hunting” & “Problem matching”

New physics course

• Summer 2006: GT School of Physics to test Matter & Interactions curriculum– Modernize course content– Help improve course outcomes

• In collaboration w/ NC State, Purdue– Examine challenges of implementing curricular

change at large institutions• Large universities � Institutional inertia � Static,

entrenched curriculum• Curriculum at large universities � curriculum at

small universities, colleges, high schools

Matter & Interactions(R. Chabay & B. Sherwood, Wiley, 2002)

• Modern, innovative introductory calculus-based physics curriculum

• In development for >10 years• Adopted by Carnegie Mellon,

NC State

Matter & Interactions

• Modern content– Atoms and structure of matter

– Macro/micro connections• E.g: Ball & spring model of solid can

connect atomic motion with elastic deformation, thermal physics

– 20th century physics• Relativistic momentum and energy• Quantum energy, atomic physics,

photons

Matter & Interactions

• Modeling– Fundamental principles

• Analyze systems starting from small number of principles, not large number of secondary formulas

• Multistep problems

– Assumptions, approximations, idealizations• Messy, real-world systems: Simplify to get

reasonable, approximate results

– Computer modeling

Computer modeling in M&I

• Analyze wide variety of systems– Including problems not soluble analytically

• Power of fundamental principles• 3D graphics: visualization of phenomena and

abstract concepts• VPython programming language

– Produce 3D graphics easily– Relatively simple syntax– Can teach novice programmers the basics in first lab

period– Freeware (see http://vpython.org)(Example )

Interactive pedagogy

• Lectures– Personal Response System (PRS)

• Labs– Tightly integrated to course– Studio environment:

• Hands-on experiments• Computer modeling• Group problem solving

• Homework– WebAssign: Online homework system

Preparation (Spring 2006)

• Postdoc (Kohlmyer)– Familiar with M&I content & logistics

• Materials– Equipment for new lab activities– Software (VPython, WebAssign)

• Advertising– Informing academic advisors– Email to eligible students– Student newspaper article (Technique 4/7/06)

• TA training

Implementation

• Summer 2006: Pilot section– M&I mechanics, 40 students (Kohlmyer)

• Fall 2006: Two sections– M&I mechanics, 120 students (Schatz)

– M&I electromagnetism, 40 students (Kohlmyer)

Expansion (2-3 yrs)

• Spring 2007: One large (>200) section of each course (tentative plan)

• Future expansion requires more manpower:– Faculty apprenticeship

• Prof. sits in on course, prepares to teach it in following semester

– Summer workshops• Train new M&I instructors, discuss implementation issues

– TA training and TAA recruitment• TAA’s: Undergraduates who previously did well in course

Assessment• Pre/post-testing w/ standardized instruments

– FCI (Force Concept Inventory)

• Common assessment tool in intro mechanics

– BEMA (Brief Electricity and Magnetism Assessment)

• Qualitative E&M test

• Open-ended evaluation:– Collaboration with researchers in GT Psych. dept.

• Impact of principle-based instruction on problem-solving• Impact of computer visualization

Impact at high school level

• Expansion � large numbers of students in M&I at GT, many who are:– transfers from other USG institutions– from state high schools

• How can high school physics best prepare students for M&I?– We’ve contacted two local high school

physics teachers:• Julie Hall, Pace Academy• Gus Dearolph, Woodward Academy

The Newtonian SynthesisOpen-ended prediction of motion into the future

)r(F vvf= Force as a function of position

t∆=∆ Fpvv

The momentum principle

ppp vvv ∆+⇐ Update momentum

t∆+⇐ vrr vvvUpdate position

do it again

Homework problems in M&I

• Often multi-step• Require analysis from fundamental

principles• Often require assumptions,

approximations, estimates

a) Make a rough diagram to show qualitatively the effect on the spacecraft of this encounter with Mathilde. Explain your reasoning.

b) Make a very rough estimate of the change in momentum of the spacecraft that would result from encountering Mathilde. Explain how you made your estimate.

c) Using your result from part (b), make a rough estimate of how far off course the spacecraft would be, one day after the encounter.

d) From actual observations of the location of the spacecraft one day after encountering Mathilde, scientists concluded that Mathilde is a loose arrangement of rocks, with lots of empty space inside. What was it about the observations that must have led them to this conclusion?

Determining the mass of an asteroidIn June 1997 the NEAR spacecraft, on its way to photograph the asteroid Eros, passed within 1200 km of asteroid Mathilde at a speed of 10 km/s relative to the asteroid. From photos transmitted by the 805 kg spacecraft, Mathilde’s size was known to be about 70 km by 50 km by 50 km. It is presumably made of rock. Rocks on Earth have a density of about 3000 kg/m3 (3 grams/cm3).

Preparation

• Equipment purchases for new lab activities– Young’s modulus apparatus

– Electricity kits (PASCO, specially designed for hands-on experiments in M&I E&M)

• Software– VPython– WebAssign: online homework system

Preparation

• Advertising– GT Academic Advisor Network

– Email to students eligible to take course– Article in student newpaper, 4/7/06

– Successful: Summer M&I Mech. and Fall M&IE&M are already full

Preparation

• TA training– 4 TAs assigned to

M&I courses in Summer & Fall

– Spring 2006: trained in

Execution

• Summer 2006– 40 student section of M&I mech. (Kohlmyer)

• Fall 2006– 120 student section of M&I mech. (Schatz)

– 40 student section of M&I E&M (Kohlmyer)

• Spring 2007– One standard large (~250 students) of each

course

Intro physics at GT

• 2 semester course– Large lecture sections (>200 students)

– Small lab sections (20 students)– Traditional calculus-based intro physics

curriculum

Modeling and macro-micro connections

Example: Ball & Spring model of a solid

t∆=∆ Fpvv

The momentum principle Computer model:

Spring-mass systemLab: Measure

Young’s Modulus of a metal wire

Thermal energy & microscopic

work (heat transfer)

Speed of sound in solids

Ball & spring model of solids Quantized

energy

Entropy (statistical

mechanics)

Preparation (Spring 2006)

• TA training– New lab activities

– VPython programming– Group problem solving

• Content of problems• Coaching students