Use of sound recordings and analysis for physics lab practices

Abstract

[EN] The study of oscillations, waves, and sound is included in most first-year courses on Physics, however, analyzing audio recordings to understand and test physics experiments in laboratory practices is not a common practice, compared for example with the use of visual techniques. In this paper, we fill in this gap showing the usefulness of the application of sound recording and its analysis in Physics Laboratory practices of first-year Engineering University studies. Sound recording is very simple and implemented in commonly available technology tools, such as smartphones. The analysis can be done with ease in free open-source applications, such as Audacity. This means that this experimental procedure can be easily implemented and extensively used, even in distance learning, which is particularly convenient in a pandemic context. In fact, we illustrate in this work how this approach let us to successfully transform two in-person lab practices into sessions that can be run remotely: the study of free fall and measurement of the coefficient of restitution of a ball bouncing when released from a certain height, and the measurement of the speed of vehicles by analyzing the Doppler effect of the sound that the motor vehicles produce. With this, we conclude that this is a powerful technique that should be considered, alone or in combination with other techniques, for instance video analysis, when planning the lab practices of Physics courses.