International competitions play an important role in the education of highly talented secondary school students, opening new possibilities of extending their knowledge in physics and other sciences. The results can be connected to the educational and scientific level of the participating countries. There are many types of competitions but here we…

A rigorous definition of mass in special relativity, proposed in a recent paper, is recalled and employed to obtain simple and rigorous deductions of the expressions of momentum and kinetic energy for a relativistic particle. The whole logical framework appears as the natural extension of the classical one. Only the first, second and third laws of…

We describe a simple case of non-localized interference produced with a glass plate and a laser beam focused on it. The proposed setup for observing interference is compact when semiconductor lasers are employed, and it is well suited for demonstration and comparison of interference in reflected and transmitted light in a large lecture-room. This…

A reexamination of simple examples that we usually teach to our students in introductory courses is the starting point for a discussion about the principle of conservation of energy and Galilean invariance. (Contains 5 figures.)

Using "hands-on" instruction in the science classroom has obvious value for both teachers and students. However, just because a type of instruction does not allow students to physically interact with objects does not mean it is not worthwhile. One method the author has found to be productive and engaging for students uses examples of historical…

The purposes of this study were to understand the nature of discourse in terms of knowledge types and cognitive process, source of utterances (student or teacher), and time use in microcomputer-based labs (MBL) and verification type labs (VTL) and to gain an understanding of the role of MBL in promoting mathematization. The study was conducted in…

We pedagogically introduce the search for the Higgs boson and the measurement of its properties which will be one of the primary goals of the Large Hadron Collider. Our presentation will be useful to the relevant graduate and senior undergraduate students studying physics, as well as researchers in this field. (Contains 1 figure.)

Reverberation within an enclosed space can be viewed as a superposition of a large number of simple echoes. The echoes that make up the sound of reverberation fall neatly into two categories, relatively loud and sparse early reflections, and relatively soft and dense late reflections. Ways in which readily available music production software can…

In the early 1990s Ruth Howes, a nuclear physicist on the faculty at Ball State University, and Caroline Herzenberg, a nuclear physicist at Argonne National Laboratory, were asked to write a chapter on the Manhattan Project for a volume on women working on weapons development for the military. Realizing that they knew very little about the women…

Photogate timers are commonly used in physics laboratories to determine the velocity of a passing object. In this application a card attached to a moving object breaks the beam of the photogate timer providing the time for the card to pass. The length L of the passing card can then be divided by this time to yield the average velocity (or speed)…

The finale of the weekly physics department seminar series at my college is my annual demonstration lecture. Normally, the front of the room is filled with apparatus, but in May 2008 I had only a giant kaleidoscope and a leaning tower of Pisa (Fig. 1) on display. Instead, there was a pile of overhead projector transparencies that showed examples…

This article examines several readily available "magic tricks" which base their "trickery" on physics principles, and questions the use of the word "magic" in the 21st century, both in popular children's science and in everyday language. (Contains 18 figures.)

Two results support the idea that the scalar and vector potentials in the Lorenz gauge can be considered to be physical quantities: (i) they separately satisfy the properties of causality and propagation at the speed of light and do not imply spurious terms and (ii) they can naturally be written in a manifestly covariant form. In this paper we…

In and with this text, I introduce the Forum that centers around a series of essays written by a high school student and an interview with his teacher all collected as part of a larger study about students' discourses with respect to (nature of) science, learning, and knowing. I provide a brief review of the original findings, which had been…

Illusionists use mirrors to create appearances that conflict with our notions of reality. This paper discusses an activity involving the Pulfrich effect that, in the end, makes use of a mirror to distinguish between appearance and reality.