Sliding down an inclined plane: a new method for measuring gravitational acceleration and kinetic friction in upper-secondary school

Abstract An essential goal of teaching experimental physics is to engage students in exploring the validity of models and refining them. To comprehend, test, and revise scientific models, students need well-designed learning activities that enable them to practice the necessary skills. In this paper, we critically review the prevalent assumption in contemporary literature that the coefficient of kinetic friction can be treated as a constant for a certain surface pair. Further, we introduce a novel approach for calculating gravitational acceleration by measuring accelerations on inclined planes. The study indicates that kinetic friction changes with different inclinations of the plane and cannot be assumed to be constant even with typical classroom laboratory equipment. Measuring the gravitational acceleration ( g ) via inclined planes can result in significant deviations if varying kinetic friction is not considered. This paper proposes a lab activity to investigate the validity of a naïve friction model, by measuring the well-defined gravitational acceleration ( g ) with controlled precision, in an upper secondary classroom setting.