Students’ ideas about prismatic images: teaching experiments for an image-based approach

ABSTRACT

Prismatic refraction is a classic topic in science education. To investigate how undergraduate students think about prismatic dispersion, and to see how they change their thinking when observing dispersed images, five teaching experiments were done and analysed according to the Model of Educational Reconstruction. For projection through a prism, the students used a ‘split image projection’ conceptualisation. For the view through a prism, this conceptualisation was not fruitful. Based on the observed images, six of seven students changed to a ‘diverted image projection’ conceptualisation. From a comparison between students’ and scientists’ ideas, teaching implications are derived for an image-based approach.

KEYWORDS:

• Physics education
• learning activities
• interview
• Model of Educational Reconstruction

Acknowledgments

I am grateful to the students who participated in the teaching experiments. I thank Prof. Dr. Florian Theilmann for checking his coding against mine. Henriette Bast posed for Figure 2, and for the drawings in Figure 5. I am thankful for the reviewers’ comments. I thank Anne Smith for proofreading.

Disclosure statement

No potential conflict of interest was reported by the author.