General Colloquium:
December 9 - 4:00pm Phys 223
(Coffee at 3:30p.m. in room 242)

Professor Ruth Chabay and
Professor Bruce Sherwood
Center for Innovation in Learning and Department of Physics
Carnegie Mellon University

Title: "Making Introductory Physics More Like Real Physics"

Abstract

The real world is complex, messy, and intriguing. Much of the excitement of physics stems from the process of trying to understand complex physical systems. This process involves constructing idealized and simplified models, making appropriate approximations and assumptions, estimating physical quantities, and testing the models to see how well they predict the observed behavior of real systems.

None of this excitement is present in traditional introductory physics courses, in which students work many repetitive, sanitized, unrealistic problems. The students themselves never engage in the process of building and testing models. Most students emerge from the introductory course with the belief that everything they have done is exact, though unrelated to the real world.

We have developed a different approach to the introductory, calculus-based physics course, in which students are engaged in modeling physical systems. Some of the physical modeling involves computer modeling, in which students write programs to model systems that they cannot treat analytically.

Another major component of the curriculum is a continual emphasis on the atomic nature of matter, and on macro-micro connections. For example, student measurements of Young's modulus are reinterpreted in terms of an effective spring stiffness which models the interatomic force. This effective interatomic spring stiffness is used in a model of the propagation of sound in a metal, and in a statistical mechanics calculation of the specific heat as a function of temperature for the Einstein model of a solid.

There is strong support for the notion that a small number of powerful fundamental principles can be used to explain a broad range of phenomena. For example, the emphasis on the atomic nature of matter makes it possible for thermal physics to be intertwined with mechanics, climaxing in an accessible treatment of statistical mechanics. Electrostatics and circuit phenomena are analyzed with the same set of concepts, rather than being treated as two separate disciplines.

Two-volume textbook:

"Matter & Interactions" by Ruth Chabay and Bruce Sherwood Preliminary edition, John Wiley & Sons 1999 http://cil.andrew.cmu.edu/mi.html

"Electric & Magnetic Interactions" by Ruth Chabay and Bruce Sherwood Preliminary second edition, John Wiley & Sons 1999 http://cil.andrew.cmu.edu/emi.html