Abstract:

One of the most important tasks in teaching physics is to use a suitable method for understanding and developing of the theoretically acquired knowledge. The Excel spreadsheets increase students’ interest in the theoretical subject taught in the class and help their learning. This paper describes two didactic tools made with Excel spreadsheets for an interactive approach of the teaching and learning of certain concepts of geometrical optics. With the first tool, we simulate the phenomena of reflection and refraction of light at the interface between two different optical media. There is a graphic representation of the path of light rays in the two optical media and the dependence of the angles of reflection and refraction on the angle of incidence. The tool also allows the simulation of the phenomenon of total internal reflection, highlighting the critical angle on the graph rendering the angle of refraction, according to the angle of incidence. The second tool facilitates the study of light refraction in the optical prism. The graph of the tool renders the angles of refraction, emergence and deviation according to the angle of incidence. Depending on the input data, using the graph, we can visualize the domain of values of the incidence angle that satisfy the condition of emergence. Moreover, the graph helps to determine the conditions for the minimum deviation of the light beam through the optical prism. The graphic representation of the deviation angle depending on the incidence angle is used as an alternative to the analytical method for determining the angle of minimum deviation. With the help of these two tools, students can easily understand the phenomena of reflection and refraction of light and clarify a number of concepts, such as the critical angle, the emergence or minimum deviation. It is thus confirmed that the facilities of the spreadsheets may be used in the study of geometrical optics. Starting on these tools, students can build their own Excel applications, in order to study other optics phenomena.

Keywords:

Spreadsheets, reflection, refraction, total internal reflection, optical prism, didactic tools, physics education.