Improvising an apparatus for teaching sound waves using smartphones

Abstract

Abstract Laboratory experience is integral to science education. However, access to quality science laboratory equipment is a major challenge faced by many educational institutions in developing countries. This paper reports on an improvisation of an apparatus for teaching sound waves using smartphones and materials that are easy to obtain from the community. The Kundt’s Tube is a traditional apparatus for measuring the speed of sound in air. In science education, it is used as an instructional tool for teaching sound waves in high school physics and introductory college physics. Our improvised Kundt’s tube utilized a Polyvinyl chloride pipe for the main tube and two smartphones for producing and sensing sound. Using the improvised apparatus, we were able to create longitudinal standing waves and measure the speed of sound in air to within 3.76% of the theoretical value. Thus, the improvised Kundt’s tube is fit for use in high school physics and general physics laboratories. In addition, the materials used are easily accessible and readily available which makes the apparatus very economical.