Transistors are semiconductor devices that form the basis of today's electronic technology. Following the first step of developing a point-contact transistor developed by Walter Brattain and John Bardeen in 1947, the development of the junction transistor by William Shockley in early 1948 opened the way for rapid progress in electronic technology.…

The Michelson interferometer is one of the key experiments in modern physics when it comes to the topic of interference (Box 1). Experiments using interferometry have a high historic relevance as well as uses in current areas of research (quantum erasers, gravitational wave detection) and are used in higher education. Because of the high cost of…

This paper is intended to foster conversations about stereotypes, prejudice, and our day-to-day work in the classroom. The focus is on sexism and how it can affect our teaching, particularly looking at physics textbooks. Maybe you are already familiar with debates around feminist movements, gender studies, patriarchy, performance, and all of those…

When we travel in a train moving at a certain velocity, we observe the stationary objects outside are moving backwards. These stationary objects seem to move due to a relative velocity. Consider that the stationary object outside the train is a man standing on the stationary floor watching a woman moving on a train. The woman on a train will see…

Our aim in this paper is to describe an opportunity for physics students and faculty to learn about an environmental issue of much current interest: the quantification, or footprint analysis, of carbon dioxide (CO[subscript 2]) and reactive nitrogen emissions. These can originate from human activities such as energy use, food consumption, and…

This note is about 1000 words in length. We have been taught that this much information is contained in a single picture. But, Fig. 1 is so rich that four separate ideas can be obtained from it! The figure appears in "The Boy's Playbook of Science" by John Henry Pepper. Pepper tells us that this shows an "assistant standing on the…

The relativistic addition of velocities is usually introduced early in the study of Einstein's special theory of relativity. The equations are simple enough, but randomly chosen velocities lead to unwieldy calculations that can dishearten the student. This paper presents tables of velocity components in two dimensions, composed of five or fewer…

A key concept in current fluid dynamics and its applications to biology and technology is a phenomenon known as wetting. Wetting is familiar from everyday life and is simply the ability of a liquid to stay in contact with a solid surface. The wettability depends on the properties of the liquid and the solid and can be characterized by the static…

Transfer of structural math knowledge to physics is difficult for students. While research suggests various improvement techniques, enhancing parallelism of algebraic structures used in physics to those studied in mathematics courses seems underrepresented. This paper proposes an alternative way of introducing wave functions as a set of parametric…

Simulations can provide opportunities for engaged exploration in physics teaching and learning. Beyond the two-dimensional world of screen-based simulations, abstract concepts like vectors (for example, of electric fields) can frequently be visualized better in a three-dimensional virtual reality (VR) environment. These visualizations can be…

Multiple initiatives contend that all students should master computational thinking, including the "Next Generation Science Standards, the K-12 Framework for Computational Thinking," and Code.org. In turn, many physics teachers have begun to explore a variety of approaches to integrating computational modeling through programming. These…

Thomas Young (1773-1829) is best known in the physics community for his double-slit experiment demonstrating the wave property of light and for his work on the tensile properties of solids (Young's modulus). His reputation as a physicist was built almost entirely upon a short, three-year period (1801-1803) of intense work as an instructor in…

Geodesy is a very active and essential research discipline in geophysics but it is not a commonly studied subject at the secondary school or junior post-secondary levels. Far more frequently, gravity and gravitational acceleration are discussed, to some extent, in elementary kinematics or classical mechanics courses. This often takes the form of…

In recent years, with the more powerful functions of smartphones, the use of sensors integrated by mobile phones as an auxiliary tool for physical experiment teaching has become more popular. Combined with the related mobile phone apps, people easily can develop and expand the physical experiment contents of mechanics, optics, acoustic phenomena,…

Recently available local positioning systems (LPS) have the potential to be used for interactive physics laboratory activities and classroom demonstrations. The Pozyx LPS combines multiple sensors with position data for any object that one of the devices is attached to. Devices referred to as "tags" (Fig. 1[a]) are mobile devices that…