Smartphone as monitor of the gravitational acceleration: A classroom demonstration and student experiment

Abstract

As the development of technology, smartphones today come with various sensors to mediate a nicer customer use. This paves the way for new perspectives on using smartphones as the laboratory tools. Accordingly, this paper presents how smartphone determining of the magnitude of gravitational acceleration (g) may be made, describes a classroom demonstration, cites a reported experiment designed to obtain the necessary data, and suggests a student experiment to calculate the magnitude of g. The depth of the mathematical analysis of the data can easily be adjusted to the level of the class such as arithmetic mean, slope of graph plotted by hand, and slope of graph plotted by excel. After conducting the experiment with 33 students, major in program of general science, faculty of education, Bansomdejchaopraya Rajabhat University (BSRU), the students report the magnitude of gravitational acceleration nearly the theoretical value (g = 9.78 m/s2 at Bangkok; provided by the National Institute of Metrology (Thailand)) with a percentage difference less than 2%. We highlight the advantage of this experiment with the use of low-cost means and everyday devices in the classroom as a way of gathering empirical data about moving objects.