Critério de resolução de Rayleigh: proposta de atividade experimental para o ensino da difração

Abstract

The teaching of physical optics is one of the most neglected areas in the teaching of physics in basic education, generally summarized in the geometric study of light and based only on mathematical relationships, far from wave concepts and focused on the phenomena of reflection and refraction of light. Such treatment has deprived students of the discussion of wave aspects and phenomena arising from this interpretation. Under the guidance of official documents such as the PCN and the BNCC, it can be said that by missing the opportunity to present content such as diffraction, interference, among others, a deficient formation is provided regarding such important phenomena within Optics. It also allows us to affirm, because they are so present in our daily lives, that we are dealing with essential themes in the training of citizens to read the technologies and phenomena that surround them. With the intention of contributing to alleviate this problem, this work focuses on two strategies to face this problem. The first of these is the proposal for an experimental activity, since the idea that the use of experimental activities is a fundamental element in science education is already consolidated, and with significant results presented in the literature. The second is to present this proposal in a contextualized way to a problem strongly linked to Astronomy, since this area has a potential to attract attention and develop students' imagination. Thus, the present work offers an educational product proposal that explores the problem of the power of angular resolution from the perspective of Rayleigh's criterion. Seeking to offer high school and higher education teachers an alternative of contextualization in the study of light diffraction, a phenomenon related to the limiting factor of our ability to resolve nearby light sources, such as car headlights on a road, binary stars, nearby galaxies in the celestial plane, planets with satellites, planetary rings, among others. From this last contextualization, a very rich motivation for presenting the problem of resolution, with a great and natural appeal to students. With the objective of, through this proposal, contributing to change the scenario of teaching Physical Optics in basic education, I present in this work results of several applications of the proposed methodology, carried out at the middle and higher education levels. Having as main focus the public of the high school in two educational institutions, one of the private network and another one of the public network of the state of Bahia.