Uma proposta de abordagem experimental para o efeito fotoelétrico: construindo conceitos de física moderna e contemporânea com LEDs e outros componentes de baixo custo

Abstract

This work presents a proposal for an experimental approach to the Photoelectric Effect based on a didactic kit capable of demonstrating the occurrence (or not) of the phenomenon as a function of the variation of intensity and frequency of light incident on a receiving material. The main objective is to provide a differentiated alternative for building knowledge about the subject. The kit, made with LEDs and other low-cost components present in everyday life, is easy to reproduce and operate, and compact enough to enable the execution of practical activities in any classroom, and is therefore very useful mainly for students and teachers of secondary education, which often do not have laboratories and equipment, either by the restriction of access or even by the lack of them. With three applications in the classroom, a methodology was developed where two mutually exclusive hypotheses that present themselves as an explanation for the phenomenon are confronted experimentally. The validity of only one of these hypotheses is proven by the responses given to two post-activity questions. The obtained results demonstrate that the students were able to understand the operation of the kit, use it to carry out the proposed activity and build their own knowledge about the subject. In addition, the criticisms and suggestions collected at the end of the process demonstrate that there has been considerable acceptance of the proposal by the parties. In order to make it accessible to physics teachers interested in its use, two scripts are additionally provided, one describing step by step the assembly of the kit and the other supporting the execution of the proposed experimental activity.