Before the advent of microcomputer-based labware (MBL), "time-of-flight" measurements for the speed of a transverse pulse on a string required elegant apparatus. This paper describes how to use an off-the-shelf MBL force sensor and a computer to perform the measurement. The data shown in this paper were collected using Vernier Software's wireless…

This is an ethnographic study of the trajectories and itineraries of undergraduate physics students at a Mexican university. In this work learning is understood as being able to move oneself and, other things (cultural tools), through the space-time networks of a discipline (Nespor in Knowledge in motion: space, time and curriculum in…

Kinematic measures of children's reaching were found to reflect stable differences in skill level for planning for future actions. Thirty-five toddlers (18-21 months) were engaged in building block towers (precise task) and in placing blocks into an open container (imprecise task). Sixteen children were retested on the same tasks a year later.…

In 1923, R.A. Millikan was awarded the Nobel Prize in Physics for his work on the elementary charge of electricity and on the photoelectric effect. Recently, historical research had a focus on Millikan's publication practice, as well as on the role of his assistant, Harvey Fletcher. Several studies have raised doubts on whether Millikan can…

We report on the physics around an incandescent lamp. Using a consumer-grade digital camera, we combine electrical and optical measurements to explore Planck's law of black-body radiation. This simple teaching experiment is successfully used to measure both Stefan's and Planck's constants. Our measurements lead to a strikingly accurate value for…

This paper presents a simple method for calculating Clebsch-Gordan coefficients for the tensor product of two unitary irreducible representations (UIRs) of the rotation group. The method also works for multiplicity-free irreducible representations appearing in the tensor product of any number of UIRs of the rotation group. The generalization to…

In a recent paper (Denny 2002 Eur. J. Phys. 23 449-58), entitled "The pendulum clock: a venerable dynamical system", Denny showed that in a first approximation the steady-state motion of a weight-driven pendulum clock is shown to be a stable limit cycle. He placed the problem in a historical context and obtained an approximate solution using the…

The Stoics of the Roman Imperial period share the imperative that education should not focus on erudition for its own sake, but contribute to the pursuit of the good life as they define it in philosophical terms. Hence these later Stoics express similar concerns about the technical and theoretical aspects of philosophy as they do about…

In a series of well-known papers, Chi and Slotta (M. T. H. Chi, 1992, 2005; M. T. H. Chi & J. D. Slotta, 1993; M. T. H. Chi, J. D. Slotta, & N. de Leeuw, 1994; J. Slotta & M. T. H. Chi, 2006; J. D. Slotta, M. T. H. Chi, & E. Joram, 1995) have contended that a reason for students' difficulties in learning physics is that students…

Typically-Perceived-Situation (TPS) refers to the situation rising spontaneously in an individual's mind when she/he first thinks of a phenomenon or concept. The purpose of this study is to go well beyond the many studies that describe conceptions of force and explore children's TPS of "force is acting on a thing" and "force is not…

The rapid compression or expansion of a gas in a plastic syringe is a poor approximation of an adiabatic process. Heat exchange with the walls of the syringe brings the gas to equilibrium in an amount of time that is not significantly greater than the length of the compression or expansion itself. Despite this limitation, it is still possible to…

Problems on the dynamics of changing mass systems often call for the more general form of Newton's second law Fnet = dp/dt. These problems usually involve situations where the mass of the system decreases, such as in rocket propulsion. In contrast, this experiment examines a system where the mass "increases" at a constant rate and the net force…

Several misconceptions abound among college students taking their first general physics course, and to some extent pre-engineering physics students, regarding the physics and applications of electric circuits. Analogies used in textbooks, such as those that liken an electric circuit to a piped closed loop of water driven by a water pump, do not…

Connecting physics concepts with real-world events allows students to establish a strong conceptual foundation. When such events are particularly interesting to students, it can greatly impact their engagement and enthusiasm in an activity. Activities that involve studying real-world events of high interest can provide students a long-lasting…

At Montpelier High School (MHS) in Vermont, students are accustomed to making changes in their school and community. Over the last six years, MHS students have participated in the Annual Winooski River Cleanup Project, the construction of a solar-powered greenhouse that provides produce for the school's cafeteria, and a thriving composting program…