Investigating Student Understanding of Sound as a Longitudinal Wave
Earl C. Coombs, 2007 MS in Physics
The field of physics education research (PER) has highlighted the discrepancy between what is taught during traditional instruction in physics, and what students understand afterward. PER has also provided alternatives to traditional instruction that are research-based and have been shown to be more effective in bringing students’ level of understanding of physics more in line with that of the scientific community. One topic that has received attention is the propagation of sound. We confirmed that students in the introductory algebra-based and calculus-based physics courses at the University of Maine have difficulties with sound propagation similar to those documented by others. We found that a relatively small percentage of the students we interviewed from a calculus-based introductory physics course used the community consensus model of particles oscillating parallel to the direction of propagation. We identified three other mental models used by the interview subjects that have been described previously. The first was a model in which sound is considered to be an entity that passes through the medium without disturbing the particles of the medium. The second was a model in which sound is viewed as an entity that pushes the particles of the medium aside as it propagates. The third was a hybrid model in which the particles of the medium oscillate perpendicular to the direction of propagation. In an extension of the work by previous researchers in this area, we examined students’ ability to predict the points at which the particles of the medium have the maximum and the minimum magnitudes of velocity and displacement from their equilibrium positions. We found that students’ ability to do so was extremely limited. To improve student understanding of sound propagation, we developed an instructional tool in the form of a “tutorial” and evaluated its effectiveness through pre- and post-testing of students enrolled in an algebra-based introductory physics course. The tutorial constructed for this purpose was found to be successful in increasing the number of students that used the community consensus model when answering questions about sound propagation. It was less successful in enabling students to make accurate predictions about particle velocities and displacements.
Recommended Citation
Coombs, Earl C., "Investigating Student Understanding of Sound as a Longitudinal Wave" (2007). Electronic Theses and Dissertations. 314.
http://digitalcommons.library.umaine.edu/etd/314