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 pre-med 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 re-tool 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 of dynamics 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.
Instructors also found room to add exercises and labs using MATLAB, the computing and programming software package used by many engineers to solve problems. Incoming engineering students are required to take an introductory computation course to learn MATLAB, so, with encouragement from the engineering professors, the physics department incorporated the software into all three courses. As a result, one of the exercises in the new physics course now directs students to use MATLAB to simulate the process of diffusion and plot the probability distributions of particles. Working through the process gives them a better understanding of how diffusion works on a microscopic level, according to Teitsworth.
The third class, which covers topics like thermodynamics, waves and optics, is not required for engineers, but it serves the needs of the 60 or so students each year who have earned Advanced Placement credit for the first two courses. The faculty felt strongly that all the students should study physics at a university level, says Dan Gauthier, chair of Duke’s physics department. So the engineering school requires them to take at least one physics course. The Applications of Physics class is a natural elective to fill that requirement.
Before the curriculum change, it was difficult for students to place out of the two introductory physics courses, even if they had very high AP scores. That’s because the AP Physics exam that prospective engineering students take doesn’t cover thermodynamics and waves—topics included in the original Duke mechanics course. It meant that top students were being forced to take introductory courses and sit through a lot of material they already knew—a sure way to breed dissatisfaction. With the change, these students now have access to a more appropriate course.
NO MORE ANGRY T-SHIRTS
While the professors have been collecting data to see whether students are learning better with the new course sequence, they have yet to establish any trends. Nonetheless, student course evaluations have given the professors a sense that the curriculum revamp is working. “There were two gains: one was in physics, and one was in the introductory computation course,” says Laursen. “The ratings went way up.” In addition, in exit surveys taken before students graduate, physics is showing up much less often on the list of things they didn’t like.
Aside from providing engineering students with better preparation, the Duke approach may well be a more conceptually sound way to teach introductory physics. Socolar—who had to write a series of lecture notes for the statics portion of the mechanics course because no textbook presented the material in the order he wanted—is convinced. “I like this way of doing it,” he says. “My gut feeling is that it’s easier to learn about vectors in the context of static force problems” instead of the way those concepts are usually taught.
Duke isn’t the only school changing the way science is taught to engineering students. Attempting to bolster retention of engineering majors, the University of Maryland has upgraded faculty used in introductory classes, incorporated design earlier on and tried to show how science will be applied in engineering. (See “Staying on Track” in the Jan. 2008 Prism for other examples.)
The new mechanics course at Duke “absolutely was relevant and complemented the engineering courses really well,” says Joseph Repp, a sophomore mechanical engineering student. Repp has a unique perspective because he decided to fulfill the electricity and magnetism requirement over the summer, when Duke only offers the version for life science and pre-med students. “It didn’t get into the MATLAB programming and was more textbook-oriented,” he says.
To the relief of the Duke faculty, the angry T-shirts disappeared a few years ago. “The feedback has gone from ‘we absolutely hate this course’ to ‘this is OK,’” Socolar says. “And comments about the labs went from ‘This is horrible’ to not many comments.” For one of the toughest and most rigorous courses an aspiring engineer will take, this is a big improvement.
Corinna Wu is a freelance writer based in Oakland, Calif.