The plasma ball in physics teaching: A classroom approach to plasma ionization

Plasma is recognized by Physics as the fourth state of matter. However, the study of plasmas in schools and universities often faces challenges, mainly due to the high cost of science and physics laboratories, which can be inaccessible to many groups of students. As a viable and affordable alternative, devices such as the plasma ball have been used in teaching this physical state of matter, even allowing the quantification of electric fields and the observation of electromagnetic waves. This study aimed to use a low-cost plasma ball in teaching a university-level Physics class, enabling hands-on experiments related to the determination of electric and magnetic fields. For this purpose, a low-cost digital sensor for electromagnetism and electric fields, a neon lamp, and a metallic coin were used. Students learned how to calculate the power of the plasma ball and explore the concepts of electric fields and electromagnetism, when present. The introduction of simple and engaging teaching tools significantly contributed to the students' involvement. They showed increased interest and ease in understanding the concepts related to the Physics of Electromagnetic Interactions (Electromagnetism), highlighting the pedagogical potential of accessible instruments in the teaching-learning process. Therefore, Physics classes must include basic, low-cost equipment or materials that can be easily constructed from readily available resources to enhance the teaching of this exact science.