Undergraduate Physics Courses Research Articles

Rethinking the arrow of time Now The Physics of Time Richard A. Muller Norton, 2016. 364 pp.

Citing shortcomings in Eddington's theory, a physicist proposes a new explanation for the existence of “now”

Western Faculty Profile: Dr. John de Bruyn

Dr. John de Bruyn is a Professor in the Department of Physics and Astronomy at Western University. His research focuses on the physics and applications of soft materials including non-Newtonian fluids and granular flow. Dr. de Bruyn teaches undergraduate and graduate level courses in physics. He also supervises graduate students, is a member of the editorial boards of several scientific journals and is an editor of conference proceedings. Jennifer Wang, a member of the WURJ Academic Affairs Committee, had the pleasure of interviewing him to learn more about his research and career.

EVALUACIÓN DEL APRENDIZAJE DE INTERFERENCIA Y DIFRACCIÓN DE LA LUZ EN EL LABORATORIO DE FÍSICA

Este trabajo presenta los resultados de una investigación referida al aprendizaje de la interferencia y difracción de la luz en el contexto de un laboratorio de física, mediante la aplicación de una propuesta didáctica con estudiantes de licenciatura en física. El diseño de las actividades experimentales ha tenido en cuenta las dificultades reportadas por la investigación educativa, como así también los aportes de la teoría de campos conceptuales de Vergnaud, la teoría de aprendizaje significativo de Ausubel y la teoría sociolingüística de Vigotsky. La investigación se focalizó en el estudio del desarrollo cognitivo de los estudiantes durante la implementación de la propuesta didáctica y la evaluación de la misma a través del desarrollo de competencias. Se usó un enfoque metodológico de tipo cualitativo, en una perspectiva interpretativa, con un diseño de tipo investigación-acción, donde el investigador actúa en el rol de docente mientras se recoge la información. Se han utilizado en forma complementaria las notas de campo del investigador, grabaciones en audio de interacciones grupales, grabaciones en video del trabajo grupal de los estudiantes, informes grupales sobre las actividades y evaluaciones individuales. Los resultados obtenidos con el análisis de contenido de los registros y la interpretación desde la teoría de campos conceptuales muestran una evolución en los esquemas de los estudiantes. Sus esquemas iniciales centrados en la óptica de rayos evolucionan hacia esquemas centrados en el modelo ondulatorio. Los resultados obtenidos con los informes grupales y con la evaluación individual muestran que todos los estudiantes han logrado desarrollar la mayoría de las competencias planteadas como objetivos de aprendizaje en la propuesta didáctica.

“I understand why people need to ease their emotions”: Exploring mindfulness and emotions in a conceptual physics classroom of an elementary teacher education program

In this manuscript we bring to focus student perceptions of salience (or lack of thereof) of emotions in the undergraduate conceptual physics course (in the teacher education program) and their relevance to teaching and learning. Our analysis of student responses to the Mindfulness in Education Heuristic constitutes a feedback loop affording the teacher reflection over his instructional practices. Hence, we ponder pedagogical tools employed by the class instructor (second author) that students identify as evoking emotional responses (both positive and negative). Furthermore, we highlight this teacher’s dispositions and his value system (axiology) that appear to bring to balance his passion for science (understood in a traditional Western way as a canon-based epistemology) and his approach to teaching that is driven by compassion towards his students many of whom perceive physics as challenging. We argue that adopting mindful disposition affords engaging in practices that assist in regulating emotions and attention that mediate learning of canonical science content. Likewise, we maintain that the instructor and his mindfulness-driven practices become a model to be replicated in his students’ future careers. In such context, mindfulness may be perceived as part of what is referred to as a hidden curriculum. It is our position, however, that the science classroom is a site where wellness-promoting practices (such as mindfulness) should receive an overt attention by becoming science content to be learned and practiced by all citizens throughout everyday life thus contributing to its improved quality. In recognizing that such position may be challenging to adopt by science educators, we present the way the second author has been grappling with reframing his thinking around teaching science. We encourage educators to utilize heuristic methodology towards reflecting on and informing their practice and as one way of exposing their students to social constructs such as mindfulness.

Widget Based Learning in Math and Physics Undergraduate Courses as Blended Learning Approach

Widget Based Learning in Math and Physics Undergraduate Courses as Blended Learning Approach

Um sistema automático de baixo custo para medidas de intervalos de tempo

São descritos a construção e o funcionamento de um sistema de aquisição de dados automático de muito baixo custo formado por uma chave óptica (photogate) ativada por luz infravermelha, do tipo convencional, e um cronômetro digital comum com 0,01 s de resolução, alterado para ser acionado e parado eletronicamente pela chave óptica. O sistema é projetado para uso em medidas de intervalos de tempo e pode ser utilizado tanto em laboratórios universitários de física experimental como nos de Ensino Médio de física.

Educação a distância na ótica discente

Resumo Este artigo apresenta parte das reflexões desenvolvidas durante uma pesquisa de doutorado que buscou respostas à questão: o que revelam os discursos de estudantes veteranos dos cursos de licenciatura em física e em pedagogia da Universidade Estadual de Maringá, Paraná, a respeito da modalidade de educação a distância e, mais especificamente, dos elementos constitutivos de cada curso? Para tanto, vinte e seis acadêmicos concederam entrevistas, que foram gravadas em áudio, transcritas e compreendidas segundo a teoria da Análise do Discurso de linha francesa, o que permitiu desvelar os sentidos que emanaram dos dizeres dos participantes da pesquisa, sem pretensão de generalizações. O objetivo foi compreender os discursos de estudantes quanto às suas experiências pessoais em cursos de graduação, na modalidade a distância, nos âmbitos estrutural, organizacional e pedagógico. Do resultado das análises, destacaram-se: a forte influência das imagens construídas ao longo da história pela escolarização na modalidade presencial; a facilidade de acesso ao ensino superior via educação a distância (EaD) e sua adequação às condições de vida dos alunos; a preferência dos estudantes pelo livro impresso e pelas videoaulas como suportes à aprendizagem; as resistências, as falhas técnicas e o uso limitado das tecnologias de informação e comunicação (TIC) como mediadores do processo de ensino e de aprendizagem; a presença de fragilidades no processo de comunicação entre tutores e alunos.

An investigation to determine the impact of concept mapping on learning in an undergraduate physics course

In recent years extensive research has been carried out to evaluate and highlight the declining number of graduates from science related courses. Following this, several initiatives have been designed and implemented throughout the Republic of Ireland to combat the problem of low retention rates in undergraduate science courses and to introduce the use of more effective instructional methodologies that promote the active role of the learner while also encouraging the facilitative role of the teacher. This paper examines Concept Mapping, one such initiative that has been implemented in the University of Limerick over the last two years. The research presented here is part of a large project that aims to explore and evaluate the potential of Concept Mapping as an educational tool in physics education. This paper, however, sets out to specificallyanswer the following research question: What impact, if any, did Concept Mapping have on four particular aspects of physics learning? The paper examines the effect Concept Mapping had on understanding theory, identifying physics concepts, linking prior and new knowledge and, finally, problem solving.

Cross section for (nearly) everyone

Both total and differential cross sections for the reflection of light beams off finite solid surfaces obtained by the rotation of a generic derivable convex function are presented. The calculations are developed using elementary notions of mathematics and are therefore suitable for introductory undergraduate university physics courses. Three particular cases are discussed as examples of the general procedure and of the possible considerations about cross sections in general and the physical properties of specific systems.

O método de Galerkin para a quantização de sistemas Hamiltonianos

Apresentamos o método espectral de Galerkin como uma ferramenta para a quantização de sistemas hamiltonianos. Este método pode ser introduzido como um tópico em uma disciplina de introdução à mecânica quântica em um curso de graduação em física. Comparado ao método de diferenças finitas, o método espectral possibilita precisão muito maior, além de fornecer expressões analíticas aproximadas para as autofunções de energia, e é suficientemente simples para ser exposto em cerca de quatro horas-aula. No presente trabalho, apresentamos o método em detalhe, aplicando-o à equação de Schrödinger para o oscilador harmônico simples e para o oscilador harmônico quártico. A precisão dos resultados é comparada aos fornecidos pelo método de diferenças finitas.

Discovering the rotation of our own galaxy

In the early twentieth century, the Dutch astronomer, Jan Oort, made brilliant use of the two most basic measurements of the motions of nearby stars. These are motions away or towards the Sun based on the Doppler effect, and motion perpendicular to the line of sight, measured as a slow change in the position of the star on the sky. He was able to draw far-reaching conclusions about the rotation and the mass of the Milky Way galaxy in which our Sun is located. His arguments and calculations were based on a simple dynamical model. This model is introduced and described in this article. It can serve as an excellent exercise in an undergraduate physics course, illustrating both mechanical principles and basic astronomy.

Overview of medical physics teaching in Brazil

Introduction:Brazil has seen a rise in the number of undergraduate courses in Medical Physics in recent years, as well as initiatives for the organization of graduation programs and clinical residencies in this multidisciplinary area. The purpose of the present study was to perform a data survey on academic training in Medical Physics in Brazil in the undergraduate, graduate, and residency levels until 2012.MethodsThe relevant information was requested for the leads of the training/teaching programs, which filled specific electronic forms. The data survey was accomplished by sending the forms to 38 educational institutions.ResultsThe majority (90%) of the contacted institutions returned their specific requested information. It was estimated an offer of 400 enroll admissions per year in the group of institutions that offer undergraduate programs in Medical Physics. Federal or state public educational institutions offer around 61% of these admissions and 39% are offered by private universities. The average number of candidate competition was estimated on 3.6 ± 3.9 applicants per place in undergraduate programs, and the student’s complete the courses in 5.1 ± 0.7 years. The average number of undergraduate degrees awarded per year is 10.6 ± 7.3. At least 80% of educational programs have compulsory internships in their curricula with average duration of 307 ± 99 hours. In the graduation programs it was verified that the average time for concluding the programs were 2.2 ± 0.2 years, 4.1 ± 0.2 years and 4.7 ± 0.6 years for the MSc, PhD and direct-PhD, respectively. The programs have CAPES ratings varying from 4 to 7. Finally, until 2012 the residence programs offered 31 positions per year and the professional development programs (not residence) provide 7 positions per year.ConclusionIt is understood that the presented numerical results offer a reliable scenario for the diagnosis of opportunities and scholarships distributions in each region of the country. These results may provide support for the improvement of resource distribution and the definition of public policies that can guide the adequacy of the distribution of courses in the three modalities of Medical Physics Education in the country.

Bouncing Back From “Deflategate”

Halfway through the 2015 AFC Championship game between the New England Patriots and Indianapolis Colts, game officials discovered that the Patriots were using underinflated footballs on their offensive snaps. A controversy ensued because the Patriots had actually supplied these balls to the game's referee just hours before kickoff. Athletes and physicists have since agreed that using underinflated footballs gives several unfair advantages to the offensive team. Media outlets have focused their attention on two possible culprits behind the deflationary debacle: either the Patriots had intentionally underinflated their supply of footballs, or the climatic conditions, coupled with the various impacts to which the balls were subjected during the course of the game, had somehow altered the internal air pressure of the balls. This controversy soon became known as “Deflategate” (the moniker makes an obvious connection to the 1970s “Watergate” scandal). The purpose of this article is to bring Deflategate into the laboratory activities of high school and undergraduate introductory physics courses. First, we provide some background information on the actual 2015 AFC Championship game and subsequent media blitz surrounding the controversy. When used in an introductory mechanics class, this information can help students contextualize Deflategate as a real-word application of the material they are learning. Next, we recast the spotlight on Deflategate from its current focus, the ideal gas law, to a new one—namely, the physics of a bouncing ball. We then use this scenario as a motivation for a fun but informative set of experiments that can be carried out using equipment already in most high school or college laboratories. The subsequent data analysis relies on three basic principles: projectile motion, conservation of energy, and linear impulse/momentum. The analysis showcases the application of introductory physics to the world of sports, brings current events into the classroom, and demonstrates how multiple problem-solving strategies can be used to examine different aspects of a single event. Finally, some experimental results are presented and discussed.

SU‐E‐E‐06: Teaching About the Gamma Camera and Ultrasound Imaging

Purpose:Instructional modules on applications of physics in medicine are being developed. The target audience consists of students who have had an introductory undergraduate physics course. This presentation will concentrate on an active learning approach to teach the principles of the gamma camera. There will also be a description of an apparatus to teach ultrasound imaging.Methods:Since a real gamma camera is not feasible in the undergraduate classroom, we have developed two types of optical apparatus that teach the main principles. To understand the collimator, LEDS mimic gamma emitters in the body, and the photons pass through an array of tubes. The distance, spacing, diameter, and length of the tubes can be varied to understand the effect upon the resolution of the image. To determine the positions of the gamma emitters, a second apparatus uses a movable green laser, fluorescent plastic in lieu of the scintillation crystal, acrylic rods that mimic the PMTs, and a photodetector to measure the intensity. The position of the laser is calculated with a centroid algorithm.To teach the principles of ultrasound imaging, we are using the sound head and pulser box of an educational product, variable gain amplifier, rotation table, digital oscilloscope, Matlab software, and phantoms.Results:Gamma camera curriculum materials have been implemented in the classroom at Loyola in 2014 and 2015. Written work shows good knowledge retention and a more complete understanding of the material. Preliminary ultrasound imaging materials were run in 2015.Conclusion:Active learning methods add another dimension to descriptions in textbooks and are effective in keeping the students engaged during class time. The teaching apparatus for the gamma camera and ultrasound imaging can be expanded to include more cases, and could potentially improve students’ understanding of artifacts and distortions in the images.

Projectile motion in real-life situation: Kinematics of basketball shooting

Basketball shooting is a basic practice for players. The path of the ball from the players to the hoop is projectile motion. For undergraduate introductory physics courses student must be taught about projectile motion. Basketball shooting can be used as a case study for learning projectile motion from real-life situation. In this research, we discuss the relationship between optimal angle, minimum initial velocity and the height of the ball before the player shoots the ball for basketball shooting problem analytically. We found that the value of optimal angle and minimum initial velocity decreases with increasing the height of the ball before the player shoots the ball.

Teaching undergraduate biomechanics with Just-in-Time Teaching

Biomechanics education is a vital component of kinesiology, sports medicine, and physical education, as well as for many biomedical engineering and bioengineering undergraduate programmes. Little research exists regarding effective teaching strategies for biomechanics. However, prior work suggests that student learning in undergraduate physics courses has been aided by using the Just-in-Time Teaching (JiTT). As physics understanding plays a role in biomechanics understanding, the purpose of study was to evaluate the use of a JiTT framework in an undergraduate biomechanics course. This two-year action-based research study evaluated three JiTT frameworks: (1) no JiTT; (2) mathematics-based JiTT; and (3) concept-based JiTT. A pre- and post-course assessment of student learning used the biomechanics concept inventory and a biomechanics concept map. A general linear model assessed differences between the course assessments by JiTT framework in order to evaluate learning and teaching effectiveness. The results indicated significantly higher learning gains and better conceptual understanding in a concept-based JiTT course, relative to a mathematics-based JiTT or no JiTT course structure. These results suggest that a course structure involving concept-based questions using a JiTT strategy may be an effective method for engaging undergraduate students and promoting learning in biomechanics courses.

Heterodyne interferometry for the detection of elastic waves: a tutorial and open-hardware project

Non-contacting acoustic and ultrasonic measurements are of interest in applications ranging from nondestructive evaluation to rock physics and medical imaging. The fundamental workings of the detector—the interferometer—are easily explained in undergraduate physics courses, but practical implementations are dominated by specialized, and commercial, devices. We present a robust and relatively inexpensive detector, which consists of a heterodyne interferometer and phase locked loop frequency demodulator, as an open-source alternative. We illustrate the broadband capabilities with the detection of ultrasonic waves in a mudstone sample, and low-frequency (100 Hz) vibrations of a piston.

A non-isochronous rocking oscillator

The behavior of an unbalanced rocking cylinder is investigated as an example of a non-isochronous oscillator. The dependence of the period on the maximum angular swing is found to be more pronounced than in the pendulum case and tunable with a suitable choice of masses and moments of inertia. Computer acquisition of the force exerted on the horizontal plane allows comparison of the dynamical behavior of the system with computational predictions. The system deserves consideration for theoretical and experimental investigations in undergraduate physics courses for the nontrivial effects arising from the displacement of the center of mass from the geometrical cylinder axis and the anharmonic character of the oscillations.

Western Faculty Profile: Dr. Giovanni Fanchini

Dr. Giovanni Fanchini is an Assistant Professor in the Department of Physics and Astronomy at Western University. He also holds the Canada Research Chair in Carbon-based Nanomaterials and Nano-optoelectronics. He is currently developing novel organic and carbon-based nanomaterials to increase solar cell performance. Dr. Fanchini teaches both undergraduate and graduate level courses in physics as well as supervises undergraduate and graduate students. Vivian Tan, a WURJHNS representative, had the pleasure to interview Dr. Giovanni Fanchini to learn more about his career in research.

Energy pumping analysis of skating motion in a half pipe and on a level surface

In this paper, an energy pumping mechanism for locomotion is analysed. The pumping is accomplished by exerting forces perpendicular to the direction of motion. The paper attempts to demonstrate an interesting application of the classical mechanics to two sporting events: a person skating in a half pipe and a person travelling on a level surface on a skateboard. The equations of motion based on simplified mechanical models are derived using the Lagrange mechanics. The energy-pumping phenomenon is revealed through numerical simulations with simple pumping actions. The result presented in this paper can be used as an interesting class project in undergraduate mechanics or physics courses. It also motivates potential new applications of energy pumping in many engineering fields.