Making a cat’s eye in a classroom

Abstract

Three plain mirrors, perpendicular to each other, reflect a beam of light back into the direction it came from. An activity is suggested where pupils can employ this feature of perpendicular mirrors and make their own corner cube retroreflector-a kind of cat's eye.

A simple piece of apparatus to aid the understanding of the relationship between angular velocity and linear velocity

“…In overcoming these challenges, developing and utilizing a piece of apparatus that could help to motivate students is an alternative solution. However, similar studies [5][6][7][8][9][10][11][12], in which suggestions are presented with the aim of consolidating physics concepts (acceleration, centripetal force etc) that are difficult to comprehend, are quite limited in academic journals. Therefore, as well as designing instructional methods, attention should also be paid to the design and production of instructional apparatus in physics education.…”

“…As in many disciplines, there are some difficulties with teaching some aspects of physics. In recent years in various academic publications [5][6][7][8][9][10][11][12], people have suggested the development and use of different teaching materials in order to remove these difficulties. For example, students encounter a significant problem when they are unable to correlate the concepts of angular velocity and linear velocity within circular motion.…”

A reflexão da luz nos periódicos de Ensino de Física: evidenciando tendências e carências de pesquisa a partir de uma revisão bibliográfica

“…O periscópio de submarinos é outro instrumento óptico que utiliza espelhos planos associados, levando Amann (1996) a discutir os vários posicionamentos que tais superfícies refletoras poderiam assumir nesse instrumento. Rovšek (2010), por sua vez, apresenta uma sugestão de associação de três espelhos planos perpendiculares entre si para explicar os princípios físicos do olho-de-gato, popular elemento de sinalização em estradas de rodagem. Hologramas também podem ser produzidos a partir de sistemas de dois espelhos (VANNONI et al, 2007).…”

A plane mirror experiment inspired by a comic strip

“…Geometrical optics is distinctive in the ease of getting immediate experimental evidences with low-cost materials and variety of inspirational sources, such as compact discs [1], solar eclipses [2], virtual mirrors [3], ethnic art [4], cyclops and triclops images [5,6], virtual images [7], selfies [8] or the retroreflector mirrors left on the Moon by the Apollo missions [9]. Our experiment derives its inspiration from a comic book panel (figure 1) which closes a storyline where Monica, the cartoon character, 'fights' against a television set that only generates a clear image if she places herself behind the unit, so she decides to use a mirror to view this image.…”