Physics

This activity was created within the framework of the "Space for Education" project, which ams at experiencing physical principles on the basis of topics related to space travel. Artificial satellites are suitable as application-oriented examples to explain the effect of gravity on their orbits. This working material deals with the orbit of the International Space Station (ISS) around the Earth. In simple calculations and representations, the students learn how the orbits of artificial satellites are created and which characteristic velocities occur. They compare their ISS results with those of geostationary satellites and discover applications of this particular orbit. Additional materials at: this https URL ----- Diese Aktivität wurde im Rahmen des Projekts "Raum für Bildung" erstellt, welches physikalische Prinzipien anhand der Raumfahrt erlebbar macht. Künstliche Satelliten eignen sich als anwendungsnahe Beispiele, um die Wirkung der Gravitation auf ihre Bahn näher zu erläutern. Dieses Arbeitsmaterial behandelt dazu exemplarisch den Orbit der Internationalen Raumstation (ISS) um die Erde. In einfachen Rechnungen und Darstellungen erfahren die Schülerinnen und Schüler, wie Bahnen künstlicher Satelliten zustande kommen und welche charakteristischen Geschwindigkeiten dabei auftreten. Sie vergleichen ihre Ergebnisse zur ISS mit denen von geostationären Satelliten und entdecken Anwendungen dieses besonderen Orbits. Weitere Materialien unter: this https URL

This activity was created within the framework of the "Space for Education" project, which ams at experiencing physical principles on the basis of topics related to space travel. It enables the students to investigate the power supply of the International Space Station. If available, they determine the current parameters of the electrical system from the telemetry of the ISS in real time. Otherwise, they can use archive data attached to the working documents. From this, they calculate the electrical power provided by the solar cells. Additional materials at: this https URL ----- Diese Aktivität wurde im Rahmen des Projekts "Raum für Bildung" erstellt, welches physikalische Prinzipien anhand der Raumfahrt erlebbar macht. Sie ermöglicht den Schülerinnen und Schülern, die Stromversorgung der Internationalen Raumstation zu untersuchen. Falls vorhanden, ermitteln sie die augenblicklichen Parameter des elektrischen Systems aus der Telemetrie der ISS in Echtzeit. Ansonsten können sie Archivdaten nutzen, die den Arbeitsunterlagen beigefügt sind. Hieraus berechnen sie die von den Solarzellen zur Verfügung gestellte elektrische Leistung. Weitere Materialien unter: this https URL

The appearance of the coronavirus (COVID-19) in late 2019 has dominated the news in the last few months as it developed into a pandemic. In many mathematics and physics classrooms, instructors are using the time series of the number of cases to show exponential growth of the infection. In this manuscript we propose a simple diffusion process as the mode of spreading infections. This model is less sophisticated than other models in the literature, but it can capture the exponential growth and it can explain it in terms of mobility (diffusion constant), population density, and probability of transmission. Students can change the parameters and determine the growth rate and predict the total number of cases as a function of time. Students are also given the opportunity to add other factors that are not considered in the simple diffusion model.

The formal definition of limit is one mathematical idea that gives difficulties to most students. Therefore, it is necessary to provide engaging activity in order to construct the students' understanding about the definition. This study aims to shed light on designing activities with dynamic geometry software to facilitate the students in discovering the formal definition of limit. Forty-eight students participated in the study. Both quantitative and qualitative data were collected from the students' responses in and attitudes toward the activities. The students' responses were gathered directly by using the dynamic geometry software whereas an online questionnaire was used to collect the students' attitudes. The results of the study then presented in this paper. Further, a set of suggestions in designing and implementing dynamic geometry environments to foster students' understanding about formal definition of limit was also proposed.

Engineering Thermodynamics has been the core course of many science and engineering majors at home and abroad, including energy and power, mechanical engineering, civil engineering, aerospace, cryogenic refrigeration, food engineering, chemical engineering, and environmental engineering, among which gas power cycle is one of the important contents. However, many Engineering Thermodynamics textbooks at home and abroad focus only on evaluating the thermal efficiency of gas power cycle, while the important concept of specific cycle net work is ignored. Taking an ideal Otto cycle and an ideal Brayton as examples, the optimum compression ratio (or the pressure ratio) and the maximum specific cycle net work are analyzed and determined. The ideal Otto and the ideal Brayton cycles, and also other gas power cycles, are concluded that the operation under the optimum compression/pressure ratio of the engine, instead of under the higher efficiency, is more economic and more reasonable. We concluded that the two very important concepts, i.e., the maximum specific cycle net work and the optimum compression (or pressure) ratio for the gas power cycles, should be emphasized in the Engineering Thermodynamics teaching process and the latter revised or the newly edited textbooks, in order to better guide the engineering applications. In the end, general T-s diagram is proposed for the gas power cycles.

These proceedings accompany the Belle II talk in the Diversity and Inclusion parallel session delivered during ICHEP 2020. This marks the first external presentation by the Belle II Collaboration, in which we present some of our data and self-reported statistics regarding diversity and inclusion. We also present Belle II's current and planned activities to aid and improve diversity and inclusion. We find that there is still a lot to be done to improve the social working environment and population representation within our collaboration and within high energy physics.

A recent paper in Sci. Adv. by Miller et al. concludes that GREs do not help predict whether physics grad students will get Ph.D.s. The paper makes numerous elementary statistics errors, including introduction of unnecessary collider-like stratification bias, variance inflation by collinearity and range restriction, omission of needed data (some subsequently provided), a peculiar choice of null hypothesis on subgroups, blurring the distinction between failure to reject a null and accepting a null, and an extraordinary procedure for radically inflating confidence intervals in a figure. Release of results of simpler models, e.g. without unnecessary stratification, would fix some key problems. The paper exhibits exactly the sort of research techniques which we should be teaching students to avoid.

The bra and ket notation introduced by Dirac and the dimensional analysis are two powerful tools for the physicist. Curiously, almost nothing is said about connections between these two topics in the literature. We show here that bras and kets have dimensions. This could help students to grasp a better comprehension of this abstract notation.

An appropriate diagram is a required element of a solution building process in physics problem solving and it can transform a given problem into a representation that is easier to exploit for solving the problem. A major focus while helping introductory physics students learn problem solving is to help them appreciate that drawing diagrams facilitates problem solving. We conducted an investigation in which two different interventions were implemented during recitation quizzes throughout the semester in a large enrollment, algebra-based introductory physics course. Students were either (1) asked to solve problems in which the diagrams were drawn for them or (2) explicitly told to draw a diagram. A comparison group was not given any instruction regarding diagrams. We developed a rubric to score the problem solving performance of students in different intervention groups. We investigated two problems involving electric field and electric force and found that students who drew productive diagrams were more successful problem solvers and that a higher level of relevant detail in a student's diagram corresponded to a better score. We also conducted think-aloud interviews with nine students who were at the time taking an equivalent introductory algebra-based physics course in order to gain insight into how drawing diagrams affects the problem solving process. These interviews supported some of the interpretations of the quantitative results. We end by discussing instructional implications of the findings.

The Force Concept Inventory (FCI) can be used as an assessment tool to measure the gains in a cohort of students. In this study it was given to first year mechanics students (N=256 students) pre- and post-mechanics lectures, for students at the University of Johannesburg. From these results we examine the effect of switching mid-semester from traditional classes to online classes, as imposed by the COVID-19 lockdown in South Africa. Overall gains and student perspectives indicate no appreciable difference of gain, when bench-marked against previous studies using this assessment tool. When compared with 2019 grades, the 2020 semester grades do not appear to be greatly affected. Furthermore, initial statistical analyses also indicate a gender difference in mean gains in favour of females at the 95% significance level (for paired data, N=48). A survey given to students also appeared to indicate that most students were aware of their conceptual performance in physics, and the main constraint to their studies was due to difficulties associated with being online. As such, the change in pedagogy and the stresses of lockdown were found to not be suggestive of a depreciation of FCI gains and grades.