Page 80 - Teaching Innovation for the 21st Century

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Teaching Innovation for the 21st Century | Showcasing UJ Teaching and Learning 2021
Introduction
The ongoing Covid-19 pandemic has made it a necessity for physics teachers worldwide to adapt their approach to teaching to incorporate a focus on technology in the delivery of the content (Ametepe & Khan 2021; Klein et al. 2021; Marzoli et al. 2021). The sudden shift, for many educators and students, to migrate to online teaching (where relevant) as imposed by the pandemic lockdowns has also highlighted the need to increase
the computer skills of both students and teachers/lecturers to face the demands of a sustained online/blended learning approach.
More broadly, widened computer literacy is necessary to be able to operate in the technology-based world that is envisaged by the advent of the Fourth Industrial Revolution (4IR). In light of the above, it is imperative for lecturers to come up with innovative ways
of delivering content that does not only cater for the need of understanding the taught discipline itself, but also fosters computer literacy while providing some kind of anchoring to reality to counteract the lack of contact classes within an online learning environment. Similar efforts in utilising open source software in teaching physics concepts have already be attempted in the past (Logiurato 2011; Casaburo 2021).
It is with the above in mind that an online activity on sound waves was developed, with the aim of studying the harmonics produced by the open A string of a cello, whose fundamental harmonic has a frequency of 220 Hz. The A string is the thinnest of the four strings of the cello, and it is located on the left-hand side of the fingerboard with respect to the player. The activity was deployed for the first time in the second semester of the 2021 academic year to second-year physics students enrolled for the annual course Physics 2Y/Physics Y2
at the University of Johannesburg (UJ) (class size = 35 students). Students were provided with audio files of the recorded sound of a cello. Following instructions and videos prepared by the instructors, students were introduced to making use of two open-source software, i.e. Sonic Visualiser and Audacity (described in section below), to display and extract the spectrogram of the harmonics. The details on how this activity was structured are found
in the section below. At the end of the activity, students were expected to submit a short report which was then marked to form part of the assessment of the course.
The activity will be described in detail in the following sections. It is important to note that the informal feedback received by the students has allowed the instructors to understand that it has improved not only the understanding of the subject matter (by providing a real- life application rather than more traditional conceptual examples), but also the enjoyment of the discipline as well as the computer skills of the students.
Description of the online activity
Open source software: Sonic Visualiser and Audacity
Sonic Visualiser is an audio visualisation and analysis software developed by the Centre
for Digital Music at the Queen Mary University of London, UK (Cannam et al. 2010). In this activity, the software made it possible for students to view audio files as a spectral plot that visualises both sound amplitude and frequency over time, see Figure 1(a).
Audacity® is a fully featured audio editor developed by the Audacity team as free open source software (Audacity, 2022). Audacity has built in Fast Fourier Transform (FFT) routines