The classical "brachistochrone" problem asks for the path on which a mobile point M just driven by its own gravity will travel in the shortest possible time between two given points "A" and "B." The resulting curve, the cycloid, will also be the "tautochrone" curve, i.e. the travelling time of the mobile…

We describe a simple experiment about sliding friction of an object moving with non-constant speed along an inclined plane. This experiment can be used to study the entire dynamical process of force and motion in various ways, depending on the mathematical level of the students. We discuss how video measurement and analysis, and mathematical…

In a kindergarten classroom, exclamations like "Oh no!" may be causes for concern. However, when the students in Mrs. Grabia's classroom shouted "Oh no!" and "Uh oh!" during an engineering-infused 5E lesson, it meant that a persistent little robot had pushed its way out of the fences they had created. It also meant…

Background: People with profound intellectual and multiple disabilities (PIMD) are at risk of being motorically inactive. This study investigated the degree and type of motor activation in daily practice and its relationship to personal and contextual factors. Method: A total of 58 participants with PIMD participated in the study. Data concerning…

[This paper is part of the Focused Collection on Curriculum Development: Theory into Design.] This paper discusses the theoretical framework and curriculum materials that form the basis of the Investigative Science Learning Environment (ISLE) approach to learning and teaching physics. ISLE, as a philosophical approach to learning, has two core…

Spontaneous motion is one of the most basic event types, but different languages use varying patterns to express it. For example, English usually encodes path information in prepositional phrases or adverbial particles, while Korean maps path information onto verbs (Talmy, 1985). This study predicts that this typological difference would affect…

Poggendorff showed experimentally, in the middle of the 19th century, that the weight of an Atwood machine is reduced when it is brought to motion. His experiment has been revisited from time to time, making use of instrumentation that reflects the technological development of the moment. In this paper, the evolution of the experiment is briefly…

My favorite exam question comes from the final exam in an introductory mechanics course: "A rolling 31 ton railroad boxcar collides with a stationary flatcar. The coupling mechanism activates so the cars latch together and roll down the track attached. Of the initial kinetic energy, 38% dissipates as heat, sound, vibrations, mechanical…

As presented in physics textbooks, as well as in a few papers, the typical example of an induced motional electromotive force e[subscript mot] = "Blv" consists of a conductive rod of length "l" frictionlessly sliding with speed v along parallel wires within an orthogonal and constant uniform magnetic field of magnitude…

Trampolines can be found in many gardens and also in some playgrounds. They offer an easily accessible vertical motion that includes free fall. In this work, the motion on a trampoline is modelled by assuming a linear relation between force and deflection, giving harmonic oscillations for small amplitudes. An expression for the cycle-time is…

In November 2014 the "Rosetta" mission to Comet 67P/Churyumov-Gerasimenko made the headlines when its "Philae" lander completed a successful unpowered descent onto the surface of the comet nucleus after "7 hours of terror" for the mission scientists. 67P's irregular shape and rotation made this task even more…

Returning to the classroom each year is an act of radical repositioning. Even as I return to the knowledge, experience, and accumulated memories of my teaching and creative practice, I look to ways to restructure how I deliver information and search for new methodologies of learning. Acknowledging the fluid conditions that define teaching movement…

Observation of the water jets flowing from three equidistant holes on the side of a vertical cylindrical bottle is an interesting and widely used didactical experiment illustrating the laws of fluids in motion. In this paper we analyze theoretically and numerically the ranges of the stationary water jets flowing from various rotationally symmetric…

Reasoning about mechanism is central to disciplined inquiry in science and engineering and should thus be one of the foundations of a science, technology, engineering, and mathematics education. In addition, mechanistic reasoning is one of the core competencies listed in the Next Generation Science Standards (NGSS) Engineering Concepts and…

In this paper, we present a case study of a pair of students as they use nondisciplinary communicative practices to mechanistically reason about binary star dynamics. To do so, we first review and bring together the theoretical perspectives of social semiotics and embodied cognition, therein developing a new methodological approach for analyzing…