Actually Understanding Physics

My scientific background is primarily in biology, with a good dollop of chemistry and a fair bit of geology thrown in. Physics was never really part of the mix for me, so when I had the opportunity to take a couple of conceptual physics classes in graduate school as part of my teacher training, I was pretty excited.

One of those classes was particularly rewarding. It was primarily a study of naked-eye astronomy (i.e., the Sun and Moon). In this class, we did some just plain awesome things- most notably, we taught ourselves to tell time by looking at the moon. Most of my classmates were like me- science teachers (or future science teachers), but not physics teachers. Few of us had any significant knowledge of physics going into the course. One student, however, was different. He was a graduate student in the physics department, not the education department.

This fellow- I'll call him John- gave me some insights into certain problems with traditional science education in general, and physics education in particular. I expected him to have a real edge in solving problems and understanding scenarios, but he did not. Without formulas to use and calculations to perform, he seemed lost. John did not have a better grasp of the big ideas in physics than the rest of the class. The only area where he showed superior performance was in mathematical ability. I don't want to underestimate the importance of math, but being able to solve equations while being unable to explain the ideas in words seems a little like being a dancer who is physically fit enough to perform breathtaking stunts, but who lacks musicality and expressiveness.

Now, I am aware that there is an excellent chance that John had been assigned to that particular introductory-level class because his professors realized that he had an unusually poor understanding of conceptual physics. Nevertheless, I think he is symptomatic of a larger problem. Too often, science classes are structured in a way that emphasizes memorization over reasoning. These classes may appear to be rigorous, but instead of promoting high achievement, they often quash interest in science and most of their victims do not retain significant knowledge after the final exam is over. Because of the focus on details of problem solving, it is possible to do well in such a class without actually seeing the big picture.

In physics, there is currently a movement to correct this problem by teaching the subject first in a conceptual way, with relatively little mathematics. The goal of conceptual physics is not to eliminate math but rather to use it as a tool in the service of ideas. In this model, all students should leave high school with the ability to discuss Newtonian physics verbally and make accurate, qualitative predictions about the physical world. Students with a desire to deepen their knowledge of physics can then go on to take more math intensive, quantitative physics courses.

Given my strongly positive experience with conceptual physics, I am obviously a proponent of this approach. Indeed, I would like to see other sciences, especially chemistry, take note of this trend. If you would like to learn more about conceptual physics, I recommend Conceptual Physics for Everyone by Paul Hewitt and Physics by Inquiry by Lillian McDermott.

Oh, and John? By the end of that class, he was more proficient at solving equations, and able to discuss physics in words, too.