The Three-Tier Open-Reason Test: Analyzing Misconceptions and Obstacles Students through Individual-Centered Written Verbal Representations on Physics Concept

This study investigates students’ conceptions of the free-fall motion concept. The three-tier open-reason test was used as an instrument to diagnose students’ conceptual understanding. A total of 20 high school students (10 males and 10 females) participated in this study. The analysis focused on individual-centered verbal written representations to uncover students’ understanding, misconceptions (MCs), and the reasoning behind their answers. The results indicate that the most dominant MCs is the belief that gravity does not act in a vacuum. While some students demonstrated partial or sound understanding, many provided guessing or non-scientific answers. Rasch analysis was employed to measure individual student abilities and map item difficulty, enabling the identification of students who require targeted interventions. These findings highlight the importance of addressing specific MCs and applying tailored instructional approaches to enhance conceptual understanding in physics.