Mechanical Object as a Learning Aid: Uncovering Students’ Mental Models Solving Thermodynamics Problems

Undergraduate students frequently struggle with thermodynamics because of its abstract nature and complicated intellectual foundations. Previous research has looked into the use of haptic technologies and hands-on workshops to improve comprehension, but these methods can be resource costly. A more accessible method is to incorporate small mechanical devices into problem-solving exercises to improve conceptual understanding. This study investigates how students' mental models evolve when solving thermodynamics problems and whether incorporating mechanical objects influences their problem-solving patterns. We hypothesize that students with access to physical objects will engage in more experiential reasoning, leading to enhanced conceptual connections. Using a sequential analysis approach, we examined 32 think-aloud sessions from third-year undergraduate students solving thermodynamics problems. Students were divided into two groups: one with access to small mechanical objects and one without. Their problem-solving sequences were coded and analyzed to identify patterns in reasoning and conceptual development. The analysis revealed that students generally followed a structured problem-solving framework, aligning with prior research. However, those with mechanical objects demonstrated increased connections between use of experiences and different problem-solving steps. Differences were also observed based student performance levels, with high-performing students exhibiting more iterative and scaffolded problem-solving approaches. Our findings suggest that even simple, inexpensive mechanical objects can positively impact students' mental models by fostering experiential reasoning. While traditional instruction often lacks tangible connections to thermodynamic concepts, introducing physical objects appears to reinforce conceptual understanding. Future research should explore how alternative representations, such as images, videos, and AR/VR simulations, compared to physical objects in shaping students’ mental models.