Newton's second law is one of the cornerstones of the introductory physics curriculum, but it can still trouble a large number of students well after its introduction, hobbling their ability to apply the concept to problem solving and to related concepts, such as momentum, circular motion, and orbits. While there are several possibilities for…

The traditional introductory-level meterstick-balancing lab assumes that students already know what torque is and that they readily identify it as a physical quantity of interest. We propose a modified version of this activity in which students qualitatively and quantitatively measure the amount of force required to keep the meterstick level. The…

It is argued that knowledge about models is an important part of a profound understanding of Nature of Science. Consequently, researchers have developed different "levels of understanding" to analyse students', teachers', or experts' comprehension of this topic. In some approaches, "global" levels of understanding have been…

Symmetry properties of molecules are generally introduced in second-year or third-year-level inorganic or physical chemistry courses. Students generally adapt readily to understanding and applying the operations of rotation (C[subscript n]), reflection (s), and inversion (i). However, the two-step operation of improper rotation-reflection…

It is hard to observe relativistic effects in everyday life. However, table experiments using a mechanical transmission line for solitons may be an efficient and simple way to show effects such as Lorentz contraction in a classroom. A kink soliton is a deformation of a lattice of several dozen or more pendulums placed on a wire and connected by a…

I describe a simple and fascinating experiment wherein helium leaks out of a rubber balloon, thereby causing it to descend. An estimate of the volumetric leakage rate is made by measuring its rate of descent.

We compare the period of oscillation of an ideal simple pendulum with the period of a more "real" pendulum constituted of a rigid sphere and a rigid slender rod. We determine the relative error in the calculation of the local acceleration of gravity if the period of the ideal pendulum is used instead of the period of this real pendulum.

By superimposing two sound waves of the same wavelength, propagating in the opposite direction, we can create an intensity pattern having a characteristic scale equal to half a wavelength: it is the diffraction limit. Recently a group from the Institut Laue-Langevin in Paris has shown that it is possible to go beyond this limit by focusing sound…

In this column, we have previously presented various examples of how physical relationships can be examined by analyzing acoustic signals using smartphones or tablet PCs. In this example, we will be exploring the acoustic phenomenon of small beats, which is produced by the overlapping of two tones with a low difference in frequency ?f. The…

Argumentation is now seen as a core practice for helping students engage with the construction and critique of scientific ideas and for making students scientifically literate. This article demonstrates a negotiation model to show how argumentation can be a vehicle to drive students to learn science's big ideas. The model has six phases:…

Use of real specimens brings the study of biology to life. This activity brings easily acquired plant specimens into the classroom to tackle common alternative conceptions regarding life, size, complexity, the nature of science, and plants as multicellular organisms. The activity occurs after a discussion of the characteristics of life and engages…

We describe an activity-based approach for teaching aqueous solubility to introductory chemistry students that provides a more balanced presentation of the roles of energy and entropy in dissolution than is found in most general chemistry textbooks. In the first few activities, students observe that polar substances dissolve in water, whereas…

Nutrition labelling, which helps consumers to make informed choices, can be used as both a context and a vehicle for students to consolidate and apply their knowledge of food and nutrition to improve health. It also facilitates students' ability to negotiate socio-scientific issues from scientific and other perspectives. This article reports a…

This study aims to explore students' argumentation and decision-making relating to an authentic socioscientific issue (SSI)--the problem of environmental toxins in fish from the Baltic Sea. A multi-disciplinary instructional module, designed in order to develop students' skills to argue about complex SSI, was successfully tested. Seven science…

Creative learning is discussed with respect to a specific physics topic. A teaching example, based on an apparatus that demonstrates the standard dynamo model of geomagnetism, is presented. It features many of the basic physics concepts within the syllabus of electromagnetism at high-school and university. To stimulate conceptual learning and to…