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This article presents an exploratory study about the use of the word “metacognition” in papers published in Science and Mathematics Teaching Brazilian journals of stratum A1 and A2 of CAPES, from 2007 to 2017. The corpus of the research was constituted of 430 papers that were analysed by the procedures of Content Analysis. Two interpretative movements were carried out: the first focused on the general intentionality of the article, exploring the contexts in which the word metacognition was used, systematized in six emerging categories: Learning Process; Metacognitive process; Teacher training; Evaluation Instrument; Learning Object and Learning Environment; the second focused on the meanings of the word metacognition presented in the articles, from which thirteen categories emerged: Metacognitive Process; Metacognitive strategy; Metacognitive Ability; Metacognitive Character; Metacognitive thinking; Learning; Metacognitive Knowledge; Teacher Metacognition; Self-regulation; Awareness raising; Metacognitive Competence; Metacognitive Model and Metacognitive Level. From these analyzes resulted what we call the „general diagram‟, which represents a synthesis of researches about metacognition published in Science and Mathematics Teaching Brazilian journals in the last 11 years.

This article presents a Physics teaching research using as teaching-learning technique a didactic sequence constructed from educational games, experimental activities and computational simulations. The content covered in this work is hydrodynamics and its application in the physical concepts involved in airplane flight. Learning content is reinforced through the use of computer simulation using the software Modellus. The students' evaluation was made with the use of educational games: crosswords, word searches and games of the seven errors. The assessment was carried out through the application of questions that evaluated the students' alternative conceptions. The theoretical framework is based on the theory of mental models of John-Laird and in the theory of meaningful learning of Ausubel. So, the evaluations of previous knowledge of the students were made through evaluation of test type questionnaire.

We present a complete Portuguese translation of the 1896 paper by Charles Édouard Guillaume (1861-1928) about the temperature of interstellar space. The importance of this work is that it is the oldest estimate known to us of the temperature acquired by a body which is in interstellar space far away from other stars. This temperature would be due to an equilibrium state in which the radiation received by this body from the stars around it would be equal to the radiation emitted by this body. This estimative happened prior to the birth of George Gamow (1904-1968) who is considered erroneously in many textbooks as being the first person to have predicted this temperature.

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This paper shows that it is possible to understand the key features of the gravitational waves emitted by coalescing binary systems from the concepts of fundamental physics. We utilize no more then the contents typically covered in introductory courses on mechanics and electromagnetism that are common to all STEM undergraduate programs. We meticulously deduce the equations required to comprehend the results announced in the paper by the LIGO Collaboration for the event GW150914. Our quantitative description is at least of order of magnitude accurate. We estimate the chirp mass of the coalescing black holes, the total mass of the system, the individual black hole masses, the size of the binary system, and the distance from the Earth to the black holes of the event GW150914. These estimates are performed by utilizing the available data for the amplitude of the gravitational waves, the frequency at the beginning of the inspiral phase, the chirp frequency, and the time until coalescence. In order to illustrate the power of our approach, we apply our quantitative analysis to the first ten gravitational waves detections announced by the LIGO-Virgo Collaboration from February 12, 2016 (discovery event) until June 20, 2020 (event GW190814). [ABSTRACT FROM AUTHOR]

El presente artículo contiene los resultados obtenidos de una investigación realizada para estudiar los efectos que produce el modelo de enseñanza-aprendizaje de la física con una estructura problematizada en la capacidad para resolver problemas y, en las actitudes e intereses de los estudiantes del primer curso universitario. Este artículo da una respuesta fundamentada a la pregunta: con una enseñanza-aprendizaje problematizada de la física, ¿se produce realmente una mejora significativa en la capacidad de resolución de problemas, y ésta, se mantiene tiempo después de la instrucción recibida?

Copyright of Acta Scientiarum: Human & Social Sciences is the property of Universidade Estadual de Maringa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Latinoamericana de Filosofía is the property of Centro de Investigaciones Filosoficas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The magnetic cannon (Gauss cannon or Gauss rifle) experiment is notable for its cross-disciplinary nature within relevant physics concepts. It is simple, quick, and easy to execute, with a rich supply of mechanics and magnetism to be observed. It has an easy-to-use structure made of a few steel spheres positioned linearly on a rail. Taking these advantages into account, this paper presents a theoretical and experimental study of the Gauss cannon for classroom application using magnetism, kinematics, and energy and momentum conservation principles. The development was based on educational models of energy conservation in the Gauss cannon and was expanded to present a model that uses the principles of linear energy conservation and the potential energy of the magnets. The end result was the acquisition of an ejection velocity equation that could be tested experimentally. It was capable of accommodating more sphere configurations than the two works observed in the literature, and furthermore, it presents a more accurate values. [ABSTRACT FROM AUTHOR]

Undergraduate Physics courses has one of the highest dropout rates in Brazilian universities. To face this problem, it is necessary a deep understanding of the causes that lead students to withdraw or persist in their undergraduate courses. Despite empirical research, the validation of a theoretical model that explains dropout and student persistence in the Brazilian context is a current challenge for researchers in the field. In this paper, we evaluate the suitability of the Tinto's Persistence Motivation Model, developed in the United States of America, to represent the scenario of an undergraduate Physics course at a Brazilian public university. We carried out a quantitative study from data collected with a questionnaire answered by 168 undergraduate students. The questionnaire brings up statements related to the predictors of student persistence according to the Tinto model (academic self-efficacy, sense of belonging and perception of curricular relevance) and the self-declared intention of persistence. Statistically significant correlations were identified between all constructs, endorsing the theory proposed by Tinto. The linear regression model was able to predict 37% of the variance of intention to persist. This indicates that the model partially represents the investigated setting. New studies must be done to identify other aspects that impact student persistence in the investigated context. [ABSTRACT FROM AUTHOR]

Copyright of Aufklärung: Revista de Filosofia is the property of Aufklarung: Revista de Filosofia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DoisPontos is the property of Universidade Federal do Parana, Departamento de Filosofia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Intuitio is the property of EDIPUCRS - Editora Universitaria da PUCRS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Internacional de Educación y Aprendizaje is the property of Eagora Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hooke's law establishes a direct relationship between the applied force and deformation triggered on an object, with the elastic constant being the proportionality factor. Introductory Physics courses usually address Hooke's law in the context of real springs. This paper proposes a complementary didactic approach to the topic "elasticity of materials", considering a microscopic model in wich the interatomic bonding behave like springs. Thus, the elastic constant of these structures can be predicted by an extremely simple closed formula in the case of periodic systems. Particularly, monolayer hexagonal boron nitride structures were modeled from a series-parallel combination of identical springs. The model was developed within the linear approach of elasticity to ensure theoretical simplicity. A study was conducted to establish an optimal value corresponding to this regime, and 1.8% was determined as the maximum strain. The model was tested via atomistic computational simulations, being able to accurately predict the values of the elastic constants of the structures. Finally, the proposed approach proved to be didactically simple and interesting in introductory Physics or Engineering courses, mainly for the confirmation of the validity of the usual rules of spring combination in the microscopic domain. [ABSTRACT FROM AUTHOR]

In this paper, we approach different ways to use optical transformation matrices, or ABCD matrices, and optical simulations as tools for teaching geometrical optics. The work presented here ranges from simple situations, such as perfect flat lenses, to more complex situations, such as optical systems in media with different refractive indices. These examples can be easily solved with the use of optical matrices, a powerful tool, yet not widespread in undergraduate physics courses in the country. We will compare results from the classical equations for thin lenses and the matrix method with the results obtained through simulation with the freeware software OSLO EDU to show the power of the matrix method. With this proposal, the teacher will have new ways of approaching the problem and will facilitate both his didactics and student learning in the classroom or optical laboratories. Approaching geometrical optics in a different way will also enable real-world applications and the introduction of optical simulation software in the classroom. [ABSTRACT FROM AUTHOR]

Copyright of Investigações em Ensino de Ciências is the property of Instituto de Fisica-UFRGS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we present a mathematical derivation of the Schrödinger equation departing from only two axioms. We also show that, using this formal derivation process, it is possible to directly derive the Schrödinger equation in generalized curvilinear coordinate systems. This derivation is also shown to be equivalent to Feynman’s path integral approach, but goes further, allowing us to mathematically derive the Bohr-Sommerfeld quantization rules. The use of a small parameter, both in the present derivation, where it is δr, and Feynman’s derivation, where it is ϵ = δt, is also clarified in terms of the Central Limit Theorem. Therefore, the article makes a didactic transposition of the topic of quantization, allowing it to be addressed in the context of teaching Quantum Mechanics. The epistemological importance of axiomatic approaches for the mathematical derivation and the interpretation of the symbols of the theory is also considered.

Faraday’s law of electromagnetic induction is one of the four Maxwell’s equations, presented here in vector notation. Its discovery paved the way for a second industrial revolution based on machines powered by electricity. Roughly speaking, it states that the negative (a Lenz‘s contribution) of the temporal rate of change of magnetic fields acts as a source for an electric field of rotational nature. In this paper, we discuss readily replicable experiments demonstrating Faraday’s law in action, using the motion of a neodymium magnet under three natural motions: i) free fall under gravity; ii) pendular motion under gravity and iii) the magnet placed at the free end of a vibrating ruler. Due to their simplicity, these systems allow for a complete theoretical treatment. We consider more than one way of calculating the induced voltage in a circular coil, by the magnet in motion. This way, students can benefit from the multidisciplinary aspects, connecting the knowledge of kinematics of motion and the electrodynamics of particles in motion. The experimental data was obtained using an oscilloscope and contrasted to the theoretical predictions. In practice, these experiments can be used to estimate the magnetic dipole moment of a permanent magnet.

ResumoIntrodução: Atualmente, ocorre no Brasil destinação inadequada de materiais da construção civil, fato que acarreta impactos negativos ao meio ambiente e, consequentemente, preocupação com a busca de métodos viáveis e sustentáveis de reciclagem e reintegração desses materiais no ciclo produtivo, bem como a verificação da influência desses materiais quando reintegrados à construção civil. Objetivo: Apresentar um possível método de reciclagem de fibras de papel kraft e analisar, através de pesquisas e testes, sua viabilidade na construção civil, considerando aspectos como a absorção de água por capilaridade. Materiais e Métodos: O estudo foi realizado com levantamentos bibliográficos e, em seguida, com testes laboratoriais para analisar a influência da adição de fibras de papel Kraft no concreto, verificando a absorção por capilaridade. Resultados: De acordo com os testes e os processos empregados, a reciclagem de fibras de papel kraft é viável, pois sua adição ao concreto não altera abruptamente as propriedades do material e atende aos padrões de umidade. Conclusão: Concluiu-se que a adição de fibras de papel kraft no concreto pode reduzir o desperdício na construção civil, trazendo benefícios ao meio ambiente e sendo totalmente sustentável. Concluiu-se também que as fibras aumentam a capacidade de absorção do concreto; por esse motivo, o valor ideal adotado para a adição de fibras é de 0,5% g, característica que garantiu melhor resistência mecânica e menor coeficiente de absorção por capilaridade.Palavras-Chave: Construção Civil; Reciclagem; Fibra de Papel Kraft; Celulose; Absorção; Umidade===========================================================================AbstractIntroduction: Currently, we have in Brazil the inadequate disposal of waste construction materials, bringing negative impacts to the environment and consequently the concern to the search of viable and sustainable methods for recycling and reintegration of these materials in the production cycle, as well as the verification of the influence of these materials when reintegrated to civil construction. Objective: To present a possible method of recycling kraft paper fibers and to analyze, through research and testing, their viability in civil construction, considering aspects such as water absorption by capillarity. Materials and Methods: The study was conducted with bibliographic surveys and then with laboratory tests to analyze the influence of the addition of kraft paper fibers in concrete checking the absorption by capillarity. Results: According to testing and processes, kraft paper fibers recycling is feasible in that its addition to concrete does not abruptly change material properties and meets moisture standards. Conclusion: It is concluded that the recycling and addition of kraft paper fibers in concrete can be applied to reduce construction waste, bringing benefits to the environment and being fully sustainable. It is also concluded that the fibers increase the absorption capacity of concrete; for this reason, the ideal value adopted for fibers to be added is 0.5% g, a trait that ensured better mechanical strength and a lower coefficient of absorption by capillarity.Keywords: Civil Construction; Recycling; Kraft Paper Fiber; Cellulose; Absorption; Humidity Autor

This paper presents a review of the literature on the use of Arduino in Physics teaching, conducted through the consultation of articles published in the main Brazilian science teaching journals. The research focused on the contributions of the use of Arduino directed to the teaching of Physics and resulted in a sample of 20 articles. The collected papers were classified into two categories: didactic proposals tested in the classroom, and didactic proposals for application in the classroom. In addition, the main objectives expected by the practices are: innovation of the didactic laboratories, interdisciplinarity and contextualization, potentiate the learning of the physical concepts, make classes attractive and motivating, obtaining data and dissemination of the Arduino. It is possible to observe that, although this technology is relatively new, there are already many publications in the area, with possible applications in physics teaching. Most, with metrological proposals focused on experimental practice, as well as, the automation of didactic laboratories. In general, in the experimental practices approached, satisfactory but punctual results were obtained. Although many innovatory didactic proposals have been made public, there are still few studies that show data regarding the learning of physical concepts through the application of the aforementioned resources in the classroom.

This paper has a didactic aim. The Einstein General Theory of Relativity is very difficult for undergraduates students and also for graduates who have not followed a course of study in gravitational physics. For example, the calculation of some of its known consequences, such as the gravitational time dilation, requires familiarity with space-time metrics. In this paper, starting with the analogy between the electromagnetic field and the inertial one, we want to analyze, through the Einstein Equivalence Principle (EEP), some simple effect in a fictious gravitational field by using the inertial potentials in analogy with the electromagnetic ones.

This paper serves as a primer on superconductivity, inviting students for further investigation. Although the theory of superconductivity is a many-body quantum theory, here we take a more didactic route based on thermodynamics and symmetry. We briefly survey the more than a century-old field and provide a one-sentence definition of a superconductor. Surprisingly, many textbooks lack such a definition, usually introducing superconductors through their properties rather than by definition. We explain the concept of an order parameter, symmetry, and symmetry breaking. Based on this, we clarify the difference between conventional and unconventional superconductors, which is frequently a confusing topic for newcomers. We provide the reader with a taste of a current research topic in the field of unconventional superconductivity and magnetism. For this, we explain the concept of time-reversal symmetry breaking in condensed matter physics, which is usually associated with a form of magnetism. Here, we show that time-reversal symmetry might be broken in superconductors, leading to magnetic properties due to superconductivity itself. For this purpose, we utilize the method of the Ginzburg-Landau theory for phase transitions. We discuss the field of chiral superconductivity and guide the interested reader to further study.

Copyright of Revista Góndola, Enseñanza y Aprendizaje de las Ciencias is the property of Gondola, Ensenanza y Aprendizaje de las Ciencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DoisPontos is the property of Universidade Federal do Parana, Departamento de Filosofia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In solving classical mechanics problems many times we are guided by a feeling of familiarity and analogies. Nevertheless, not always this a good strategy. This is the case of the problem of two masses in free fall in a uniform field which we discuss in this paper. [ABSTRACT FROM AUTHOR]

In this paper, we propose the development of a low-cost acquisition system using Raspberry-Pi 3 and MEMS accelerometers to measure vibrations in mechanical systems. The main objective is to assemble a signals acquisition system easy to handle, of low cost and good accuracy for teaching and industrial purposes. The central idea is that the signals are acquired and processed in the Raspberry-Pi. The Python language and numerical libraries (scipy, numpy and matplotlib) are used for implementation of acquisition and signal processing. This paper proposes the study of vibrations in time and frequency domain. The acquisition system proposed can be easy implemented and the results obtained had good precision (time and frequency domain) and agree with the literature.

This paper aims to show the essential aspects of the development of the physical concept of energy, in order to subsidize the choice of teachers about the best way to understand and teach this concept. We will study the thought of some of the main scientists who were interested on the subject, and the emerging debates around this topic. The paper is divided in two parts. Firstly, some contributions of Thomas Young, Johann Bernoulli, Galileo Galilei, René Descartes and Leibniz will be analyzed. Moreover, the evolution of the physical concept of energy in the context of machines and beyond the mechanics will be presented. The main idea that guides the discussion of this text is the fact that the development of the physical concept of energy is closely related to the development of the principle that there is a "constancy in the midst of change". That is, something is always constant despite changes in the environment. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciência em Extensão is the property of Revista Ciencia em Extensao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract In a recent paper, I have shown that the electric field at the surface of a charged conducting sphere evaluates to half the field discontinuity across the surface of the sphere. This exact result has been found by solving an improper integral, which has been criticized by Assad in a very recent paper in this journal [6]. In this note, I present a simpler approach that yields a proper integral for that field. This integral also evaluates to exactly half the field discontinuity, contrarily to Assad's objections.

Abstract In this paper we show how the IBM superconducting chips can be a powerful tool for teaching foundations of quantum mechanics for undergraduate students (for graduates as well, in some cases). To this end, we briefly discuss about the main elements of the IBM Quantum Experience platform necessary to understand this paper, i.e., how to implement operations and single-qubit measurements. We experimentally study the dynamics of single spin systems interacting with static and time-dependent magnetic fields. First, we study the resonant behavior of a single spin coupled to a time-dependent rotating magnetic field. To end, we study the Larmor precession phenomenon. In both cases we show the theoretical and real experimental implementation. This article could be useful in introductory courses on quantum mechanics and nuclear magnetic resonance foundations, for example.

This paper presents a computational simulator to demonstrate properties of a two-dimensional ideal gas from the equation of state for 2D case, allowing to view the obtaining of macroscopic quantities from the microscopic perspective of collisions according to Newton’s law. An equivalence between 2D and 3D approaches are available, as well as the Maxwell-Boltzmann velocities distribution modified for 2D. The paper describes some operational aspects in Javascript/HTML, the measure units for 2D case and a further analysis of collisions behavior with the recipient 2D borders, showing that the number of collisions with the borders isn’t a constant along the simulation.

In this paper, we discuss the application process of a didactic sequence for teaching young people and adults about Optics at high school level. The sequence incorporates teaching strategies such as video exhibition, reading and discussion of science popularization papers, demonstrations and reconstruction of experiments. The activities take into account the contextualization of physics concepts to everyday phenomena, developing the student’s intellectual autonomy and critical reasoning. In this sense, we use the sociohistorical theory of Vygotsky as a reference, as it associates the apprenticeship and the individual’s development with his social interaction. Two activities of the sequence we consider essential are: the pre-test questionnaire, identifying the students’ needs, as well as their spontaneous concepts about optics; and the post-test questionnaire, which made it possible to identify a tendency of learning in most of the students, indicating an initial process of scientific concepts construction from spontaneous ones.

Einstein’s cosmological constant, introduced by him as a strategy to keep his model of the universe as static, has been considered one of the biggest blunders throughout his career. In 1922, Einstein evaluated the paper submitted by Friedmann to a German journal, in which he showed that there is one solution to the general relativity field equations in which the size of the universe increases with time. Einstein initially considered Friedmann would have made mistakes during calculations, but after discussing this issue with one of Friedmann's colleagues, Einstein admitted he was wrong and accepted the expansion of the universe as a mathematical possibility. However, he believed it hardly could have any physical meaning. This historical episode was adapted to high school physics classes through the creation of a didactic game. In this paper, we analyze arguments about the opposition between Einstein and Friedmann and students conceptions about the role of errors in science. There was equilibrium between supporters of Einstein and Friedmann. Many of Einsteins fans had a naive admiration, believing that such a smart scientist could not make mistakes. On the other hand, Friedmann fans valued his critical attitude, challenging the authority of famous scientist. Students debated whether the fact that Einstein admitted his mistake should be valued. Therefore we noted interesting students' arguments about the role of errors in science, which motivated the problematization of the myth of genius who never make mistakes and whose authority shall never be questioned.

We describe a low-cost and playful apparatus for geometrical optics experiments that uses everyday materials. The experimental setup is simple and easy to manipulate, and it entails making spherical lenses with Jell-O. Using paper templates, created in the desired shape, we cut the Jell-O in the format of a spherical lens. Using these materials, we measured the refraction index of the lenses using Snell's Law and measured the focal distance of a convergent Jell-O lens. Using a Jell-O lens, we simulated how the crystalline lens in the human eye works. By stretching and compressing the Jell-O lens, it is possible to observe a change in the focal position, illustrating the mechanism of accommodation that occurs in the human eye. [ABSTRACT FROM AUTHOR]

Spring associations are often explored in Physics teaching through a theoretical model that defines the equivalent elastic constant of a set of springs in parallel as the sum of the spring constants of each of the associated springs. Like any scientific model, this representation is constructed by assuming a series of idealizations that delimit its validity domain. In the mentioned model, it is assumed that, when a force is applied, the associated springs extend equally, that is, they present a same deformation. For the case where two springs are used to sustain an object vertically, we will hardly have this condition respected In this paper, we present a discussion about the association of two springs in parallel from the perspective of the Bunge modeling process. We propose an expansion of the traditionally explored theoretical model considering the association of two parallel springs that do not deform equally. We also present an empirical comparison of the traditional model and the proposed expanded model. We understand that the discussion built has the potential to, besides providing the mobilization of basic physics knowledge, foster discussions about the representational role of scientific knowledge, enabling situations that demand reflection on the nature of Science. [ABSTRACT FROM AUTHOR]

Copyright of Revista Electrónica de Enseñanza de las Ciencias is the property of Revista Electronica de Ensenanza de las Ciencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DoisPontos is the property of Universidade Federal do Parana, Departamento de Filosofia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This is the third article in a series dedicated to examining the use of the delta function in the physics literature. Here we discuss the appearance of a delta function in the second derivative of the wave function if its derivative is discontinuous. When this happens it is often claimed in the literature that the proposed wave function must be eigenfunction of an operator that contains a delta function and, in some cases, it is rejected. We study in this paper what we believe are alternatives ways to deal with this situation.

This paper approaches a periodic inductor-capacitor circuit with N-coupled loops. Kirchhoff’s voltage and current laws are used in order to obtain N-coupled second-order differential equations. These equations are decoupled by using a standard discrete sine transformation. Then the voltages and currents along the circuit are written as linear combinations of harmonic waves whose normal frequencies were determined. There are N of these frequencies that depend not only on the values of the capacitance and inductance but also, on how these elements are connected. Furthermore, one presents how each normal frequency can be synchronized using external batteries that initially charge the capacitors. Additionally, not only the analytical results are presented, but also, all circuits were simulated, using the free online platform Multisim, to corroborate the analytical calculations. Further, the simulations present a way of exploring the complex subject of coupled oscillations without dealing with all the analytical calculations. Moreover, one explores interferences that produce beats in the oscillating voltages in the circuit. Finally, a general interpretation of how the currents flow in the circuit is presented when a single normal mode is excited.

In this paper, we expose and compare two different physical interpretations of Bernoulli’s equation. One interpretation is that pressure must be a type of potential energy density, and Bernoulli’s equation means the uniformity of the mechanical energy density in each streamline. However, the pressure behaves as potential energy density only for steady flows, a situation that includes Bernoulli’s equation. Another interpretation is that pressure is not a type of potential energy density, the mechanical energy density changes along the streamlines, but the work from pressure balances the energy variation. The last interpretation implies that enthalpy density is uniform in each streamline. We conclude that the two interpretations are valid, it is not possible to exclude a particular interpretation, and both of them do not violate the law of conservation of energy.

In this paper, we present a detailed deduction of the Cahn-Hilliard equation. It is a non-linear partial differential equation that continuously describes the dynamics of spinodal decomposition, i.e., spontaneous phase separation, of a binary mixture. From such an equation we can model systems that undergo phase separation toward the equilibrium, i.e., passive systems, and systems that are kept out of the equilibrium by the presence of either external forces or chemical reactions, i.e., active systems. To accomplish our main goal, we present the main concepts of non-equilibrium thermodynamics and from that, we obtain the Cahn-Hilliard equation by defining a general equation for the transport of matter and calculating the free energy for a homogeneous and non-homogeneous mixture of real fluids. By the end, we perform simulations of the Cahn-Hilliard equation and present two examples of passive and active systems that (quasi) suppress Ostwald ripening.

The professional activity that the cardiovascular surgeon performs is much more than a simple gesture to mechanically operate the patient's heart. There is in every act of intraoperative most notions of physiology and physics than we generally realize. This paper discusses, in the light of mathematics, on the dynamics of fluids, ie blood, focused on invasive measurements of blood pressure, the effect of vessel size on its internal resistance and the flow passing through it in conversion of various units of measurements of pressure and resistance, blood viscosity and its relationship to the vessel, hemodilution, differences in laminar and turbulent flow, velocity and blood pressure and wall tension after a stenosis and the origin of poststenotic aneurysm. This study is not to enable the reader to the knowledge of all physics, but to show it as a useful tool in explaining phenomena known in the routine of cardiovascular surgery.

A few papers have presented results of teaching Quantum Mechanics in High School. As a high abstraction level is demanded, it is necessary to reconsider theoretical assumptions, approaches and methodologies, in order to reduce difficulties in its insertion. This paper presents the achievements of a research, which is a didactic proposal for High School comprising discussions about Quantum Mechanics, involving elements that relate Physics and some paintings of Salvador Dalí. Embracing the relations between Physics and Art allows us to approach and express the relations between scientific education and culture with alternative ways to enrich the knowledge meaning, also aiming to provide students with a broader view about the scientific knowledge construction in an intelligent dialogue with the world. To do so, the proposal presents an operative methodology, approaching science as a historical and social knowledge to teach quantum mechanics, and it aims to make the student able to hypothesize, conceptualize, situate scientific explanations in time, in short, operate according to the provided tools. Working with the ways in which Physics, introduced as a cultural component, influences the interpretations of macro and microscopic phenomena and contributes to the understanding of Modern Physics, part of twentieth-century Physics. Therefore, adding cultural elements to Physics world seems to be increasingly necessary, as it seems to resignify it by rehumanizing its knowledge. In addition, using the historical context seems to give us a greater extensiveness to knowledge, since it also starts being part of a broader culture, beyond its scientific meaning.

Traditional teacher-centered methods, characterized by lecturing and resolution of a huge number of exercises as content fixation activities, are still omnipresent in physics classes from high school to college level, even though the efficiency of this method is low. Such methods contribute, among many others factors, such as social, economic and cultural, to high rates of failure, dropout and demotivation of the students, which denotes the importance to rethink about this practice. Several active teaching methods have shown positive results regarding the learning of contents and skills building by the students. However, these methodologies are mostly unknown by Physics teachers in Brazil. The purpose of this paper is to present one of these methods, the Team-Based Learning (TBL), which is highly widespread in health and business courses in North American Universities. It aims to improve learning and develop collaborative skills through preparatory activities, problem solving (individually and in small groups), among other strategies. In this paper, we describe in detail the method and present the main results of the scarce literature in Physics Education.

This paper, which was partially presented at the lll Simposio de Investigadores en Educación en Física, is a review of studies published in Proceedings, poster presentations and workshops that have taken place at the Reuniones Nacionales de Educación en Física (REF) of the Asociación de Profesores de Física de Argentina (APFA) in the last ten years.The categories used in papers classification in each event are also analyzed as well as a global classification by the application of the same categories to all papers and workshops is made. The results show that more emphasis is put on how teaching is made an what is learned than on about what contents teaching and leaming occur. As Physics Education can't be done without Physics, we should be concemed about these results.

The aim of this paper is to report and discuss qualitative methodological procedures used in naturalistic research. It is based on two studies concemed with an innovative approach in teaching introductory physics at university leve!, which use videotape recording for data collection.The paper describes the procese of data analysis from a qualitative perspective and goes on to reflect on, and discuss, procedures of analysis of videotaped data in the context of educational research in the field of physics education at university leve!.

When Shakespeare chose Venice as the location for Othello and The Merchant of Venice, the republic corresponded to Renaissance ideals of freedom and stability. Discoveries in the realm of geography and astronomy required a re-evaluation of the place occupied by women and men in the new conception of the universe. This essay intends to discuss the mythical Venice of Shakespeare's imagination, a symbolic landscape, less physical and concrete than ideological. In this sense, this paper turns to Foucault's concept of heterotopia to illustrate how the anxieties of an epoch were projected in the representation of the city. Here, jurisprudence is of central importance. [ABSTRACT FROM AUTHOR]

This paper aims at investigating the nature of metaphor in scientific papers in the field of Physics. We started from the assumption that metaphors are not linguistic embellishments rather performers of diverse cognitive and discursive functions. More explicitly, in this paper we explore the incidence of metaphors on the selected text and we suggest ways to addressing and analyzing this phenomenon from a discursive-cognitive perspective. We have used the contributions of Cognitive Semantics, more specifically the theory of Conceptual Metaphor by Lakoff (1980) and collaborators. We have used as corpus a paper from a physics journal which is a reference in the area in Brazil and it is available at the CAPES periodicals website. [ABSTRACT FROM AUTHOR]

The so called modern physics is at present included in the curricula of high school. Therefore, we often organize in-depth lessons on quantum mechanics and on the special theory of relativity (SR). In the following sections, we want to show a lesson given by the first author of this paper. He proposes to students a proportion to deduce relativistic time dilation and length contraction without knowing the Lorentz transformations.