Identifying students’ mental models of sound propagation: The role of conceptual blending in understanding conceptual change

We investigated introductory physics students’ mental models of sound propagation. We used a phenomenographic method to analyze the data in the study. In addition to the scientifically accepted Wave model, students used the “Entity” model to describe the propagation of sound. In this latter model sound is a self-standing entity, different from the medium through which it propagates. All other observed alternative models contain elements of both Entity and Wave models, but at the same time are distinct from each of the constituent models. We called these models “hybrid” or “blend” models. We discuss how students use these models in various contexts before and after instruction and how our findings contribute to the understanding of conceptual change. Implications of our findings for teaching are summarized.

Figure 1

A student’s drawing of sound “working its way through” by “finding little open areas” in between the wall particles.

Figure 2

The change in model states due to instruction.

Figure 3

(Color) Mental model states.

Figure 4

Picture available to students for better understanding of the situation and for optional drawing during discussion related to context 1 in interview protocol.

Figure 5

Picture available to students for better understanding of the situation and for optional drawing during discussion related to context 2 in interview protocol.

Figure 6

Picture available to students for better understanding of the situation and for optional drawing during discussion related to contexts 3 and 3a in interview protocol.

Figure 7

Picture available to students for better understanding of the situation and for optional drawing during discussion related to context 4 in interview protocol.

Figure 8

Picture available to students for better understanding of the situation and for optional drawing during discussion related to context 4a in interview protocol.

Figure 9

Picture available to students for better understanding of the situation and for optional drawing during discussion related to context 5 in interview protocol.

Figure 10

Picture available to students for better understanding of the situation and for optional drawing during discussion related to context 5 in interview protocol.

Figure 11

Student’s drawing over provided template to illustrate the statement (Ashley).

Figure 12

(Color) Student’s drawing over provided template to illustrate the statement (Hope).

Figure 13

Student’s drawing over provided template to illustrate the statement (Jewel).

Figure 14

Student’s drawing over provided template to illustrate the statement (Hope).