a more tempting science

ASEE Prism, Apr 2008 by Wu, Corinna

BOWING TO STUDENT DEMANDS, DUKE REVAMPS PHYSICS FOR A BETTER FIT WITHIN ENGINEERING.

Slogans on college students' T-shirts can be mystifying-inside jokes about beer, sports or naked-co-ed-whatever. But one T-shirt worn at Duke University left no doubt as to its meaning: "Physics Sucks." It proclaimed for all to see the widespread dissatisfaction among Pratt School of Engineering students with a key course requirement.

If the students had been merely complaining about the rigor of physics, the faculty might have brushed off their protest. But surveys and focus groups conducted during a 2001 curriculum review revealed a legitimate gripe: The gulf between the introductory physics courses and the rest of the engineering curriculum had grown so wide that students' needs were no longer being met.

"One thing we learned from students was that the course wasn't well enough connected to the other things engineers were doing in the curriculum, either at the time or afterwards," says Tod Laursen, Pratt's senior associate dean for education.

So the physicists and engineers at Duke got together to hammer out curricular changes that would make physics a better fit in engineering studies, exploring fewer topics but in greater depth.

a middle ground solution

There was no way physics would be abandoned. Every engineering student is required to take physics because the science is inextricably linked to engineering. Its principles of mechanics, electricity, magnetism, and thermodynamics undergird all technology.

Nonetheless, physics and engineering departments have traditionally had separate histories, goals and interests. Physics departments are usually part of a college of arts and sciences, administratively separate from engineering schools. And physicists and engineers often take very different approaches to similar material. Physicists emphasize fundamental principles, while engineers stress the applicability of concepts to real problems.

Duke offers three separate physics sequences, depending on whether students plan to major in physics, engineering or premed and life science. Engineering students had been taking two semester-long physics courses, one focusing on mechanics and thermodynamics and a second covering electricity and magnetism with some wave theory thrown in.

When the physics and engineering instructors sat down to retool the curriculum, they agreed that the physics courses needed to be made more relevant to engineering. But the physics faculty were determined that the courses had to be taught from a physicist's perspective. "We weren't going to back down on that," says Joshua Socolar, associate professor of physics. "On the other hand, the engineering faculty were saying, 'If what you mean is teaching a course that our students can't stand, then we'd rather just teach it ourselves.'"

After considerable discussion, the two sides found an alternative. They decided to stretch the original two-course engineering physics sequence into three courses: introductory mechanics; introductory electricity, magnetism and optics; and applications of physics. "The impetus was to try to get students to feel that physics was about principles and concepts that you can apply to many situations," Socolar says. Most engineering students now take the mechanics class in the spring semester of freshman year and the electricity and magnetism class in the fall of sophomore year.

greater relevance and depth

This revamp meant removing about one-third of the material traditionally taught in the first semester. The course became "relentlessly mechanical -no thermodynamics, no fluids, no waves," Socolar says. "What we did not do is simply remove those things and make the course two-thirds as hard. Instead, we added in some topics that flowed more easily in the context of discussions of mechanics." One such change occurred in acquainting students with harmonic oscillators. Like a pendulum, harmonic oscillators are a classic example of a mass on a spring moving back and forth-and thus, a standard part of any introductory physics class. But the new course takes students further, demonstrating the result of a combination of two or more oscillators. "These are the sorts of things not in the introductory textbooks, but [that] we felt fit in a mechanics course and are equally important from a conceptual point of view," Socolar comments.

Another change entailed a greater focus on statics - identifying the forces on objects at rest. From a physics perspective, statics is treated as a special, simple case ordynamics in which the motion of an object is zero. But statics plays a key role in engineering, so devoting more time to the topic allowed engineering students to explore a side of physics that is highly revelant to their study.

"Boy, we really saw the effect of that," Laursen says. "The jump start that that gave the kids in terms of being really prepared ... It did make a huge difference."

Focusing on fewer topics also paid off for students in the second introductory course. Stephen Teitsworth, who coordinates the class in electricity, magnetism and optics, has observed the benefits: "The students' concept of an electric field - what it is, how to use it, how to compute it-electric potential, electromagnetic waves. ... I think they emerge from this course with a more solid and mathematically precise grasp of these concepts," he says.