Students form a more exact idea of the action of optical mirrors if they can observe the wave field being formed during reflection. For this purpose it is possible to organize model experiments with flexural waves propagating in thin elastic plates. The direct and round edges of the plates are used as models of plane, convex and concave mirrors.…

Physics students encountering electric circuits for the first time often ask why adding more resistors to a circuit sometimes increases and sometimes decreases the resulting total resistance. It appears that these students have an inadequate understanding of current flow and resistance. Students who do not adopt a model of current, voltage, and…

Finding topics that inspire students is an important aspect of any physics course. Virtually everyone is fascinated by "Tyrannosaurus rex," and the excitement of the class is palpable when we explore scaling effects in "T. rex" and other bipedal theropod dinosaurs as part of our discussion of mechanics and elasticity. In this…

In this clinical study on helping students prepare for an exam, we compared three different treatments. All students were asked to take a practice exam. One group was then given worked-out solutions for that exam, another group was given the solutions and targeted exercises to do as homework based on the result of their practice exam, and the…

Shadows can be found easily everywhere around us, so that we rarely find it interesting to reflect on how they work. In order to raise curiosity among students on the optics of shadows, we can display the shadows in 3D, particularly using a stereoscopic set-up. In this paper we describe the optics of stereoscopic shadows using simple schematic…

While video games have become a source of excitement for educational designers, creating informal game experiences that players can draw on when thinking and reasoning in non-game contexts has proved challenging. In this paper we present a design principle for creating educational video games that enables players to draw on knowledge resources…

As is true of a far more famous story, it all began a long time ago, in a galaxy far, far away. It even involved a binary star system. A small star, called a white dwarf, had become a burned out husk of its former self and it turned to gorging on hydrogen and helium from its bloated red giant neighbor. The transferred gas reignited the fires of…

Engaging freshman and sophomore students in meaningful scientific research is challenging because of their developing skill set and their necessary time commitments to regular classwork. A project called the Chondrule Analysis Project was initiated to engage first- and second-year students in an initial research experience and also accomplish…

Young children distinguish between the physical and biological domains of knowledge. The current study examines how this distinction is expressed in a story construction task. Three- and 4-year-olds were shown pairs of pictures, one that depicted a normal event and one that depicted an event that violated either physical or biological causal…

The damped oscillator is discussed in every high school textbook or introductory physics course, and a large number of papers are devoted to it in physics didactics journals. Papers typically focus on kinematic and dynamic aspects and less often on energy. Among the latter, some are devoted to the peculiar decreasing behavior of energy…

The effect of the aerodynamic drag force on an object in flight is well known and has been described in this and other journals many times. At speeds less than about 1 m/s, the drag force on a sphere is proportional to the speed and is given by Stokes' law. At higher speeds, the drag force is proportional to the velocity squared and is…

It is a known fact that it takes a greater effort to run on an exercise treadmill when it is inclined with positive slope than when it is in a horizontal position. The reason seems simple: walking on an inclined treadmill is somehow equivalent to walking up a hill with the same inclination; when we walk up a hill, our own weight does negative work…

This paper deals with the joint construction of knowledge by the teacher and the students in a physics classroom. It is focused on the status of epistemic certainty/uncertainty of knowledge. The same element of knowledge can be introduced as possible and thus uncertain and then evolve towards a status of epistemic certainty; the status of other…

Calculus students' difficulties in understanding integration have been extensively studied. Research shows that the difficulty lies with students understanding of the definition of the definite integral as a limit of a Riemann sum and with the idea of accumulation inherent in integration. We have created a set of manipulatives and activities…

In this forum piece, we respond to Karin Due's study of social dynamics in groups of students in physics class and gender issues that play out in this context. We discuss two threads that appear in Due's paper: one pertains to patterns of talk within groups and how these patterns open up possibilities for learning, the other pertains to…