Why Is Physics Difficult? Some Reflections About the Cognitive Bases of Learning and Teaching Physics
Listed in
This article is not in any list yet, why not save it to one of your lists.Abstract
The study of physics is generally considered more difficult than that of mathematics, probably because the former is not a “deductive” discipline, even if it is often presented, at least in high school, as if it were a branch of mathematics. Does the difficulty lie in how it is taught or are there inherent difficulties in its learning? First of all, it must be borne in mind that physics teaching (in universities and high schools) is only minimally based on a scientific approach, and largely based on little-verified practices. Perhaps as a consequence, students often seem to behave in a “schizophrenic” way: they are able to solve the physics problems, when they are presented in formal and mathematical terms, but they radically mutate their approach if the problem is even slightly changed, use “un-physical” approaches when the problem is formulated in “everyday terms”, and the approach methodologies can change, depending on the context. From this a certain uselessness in teaching physics derives. This is probably not true for physics students, who probably would learn the same even without the courses, but holds for other students. This feeling is confirmed by the results of the _Force Concept Inventory_, a test to measure how much Galilean physics is used to interpret everyday events. The test is administered before and after a high school or university course, and the performance increase is modest. Researches on cognitive sciences suggests that the “errors” of students are due to generic mechanisms, which are also active in other contexts, whose knowledge could be very useful in teaching physics. In this article we try to highlight some of these processes, without claiming to be exhaustive or complete. The aspect that we think is the most important, is that learning physics is actually largely made up of the “un-learning” of intuitive associations, or rather, of the contextualization of intuitive physics, which cannot be eliminated since, after all, it is what allows us to survive. A good percentage of colleagues, all with many years of teaching behind them, answered absently yes, except of course correcting their answer when we asked them if they were really confident about their answer (the force is the same in the two configurations, but in (a) it accelerates both the masses \(M\) and \(m\)). The difficulty of physics therefore does not have much to do with the study. Of course, it is necessary, but that’s not all. After all, physics is based on a few laws, which must be mastered, with a learning mode similar to that used to learn the game of chess. As in the latter case, we must practice, to be able to apply the laws and their mathematical derivation in an intuitive way, but unfortunately for physics this is not enough. Physics, unlike chess, is “too” similar to reality, and contrasts with the intuitive physics modules that all of us (animals) carry from birth, as well as contrasting with other cognitive processes that hinder the learning of many other scientific disciplines. Let’s see below what they are and how (maybe) this situation can be remedied.