Free fall misconceptions: results of a graph based pre test of sophomore civil engineering students

Abstract

A partially unusual behaviour was found among 14 sophomore students of civil engineering who took a pre test for a free fall laboratory session, in the context of a general mechanics course. An analysis contemplating mathematics models and physics models consistency was made. In all cases, the students presented evidence favoring a correct free fall acceleration model, whilst their position component versus time, and velocity component versus time graphs revealed complex misconceptions both on the physical phenomenon and it's implicit mathematics consistency. The last suggests an inability to make satisfactory connections through definitions between graphed variables. In other words, evidence strongly suggests that students are perfectly able to memorize the free fall acceleration model, whilst not understanding it's significance at any level. This small study originated the develope and validation of a tutorial on free fall graphs for position, velocity and acceleration models, as part of a following cross universities major project.