We developed and field-tested an active learning exercise designed to provide biology students with the opportunity to consider key aspects of the nature of science as a method of inquiry, particularly the roles of observation and inference in the development of scientific explanations and how scientists deal with uncertainty. In the activity…

When a ball bounces obliquely on a horizontal surface, the bottom of the ball stretches horizontally and then vibrates backward. The resulting ball spin depends sensitively on the transverse vibration frequency. A simple model is presented to describe the effect, showing how the stored elastic energy can result in additional spin.

Archimedes' principle states the buoyant force is equal to the weight of fluid displaced by the object. In this work, we will develop this principle using energy considerations.

A well-known conclusion from elementary ballistic trajectory analysis is that the horizontal range of a projectile is maximized for a launch angle of 45°. The derivation of this result assumes that the launch speed is the same for all possible launch angles, but this neglects the fact that the work done against gravity by the launching mechanism…

In the transition from classical to modern physics, the idea of taking some certain quantities as distinct or bounded values and keeping the rest continuous has proved useful in dealing with many problems. In this paper we assume an upper bound on the velocity of classical particles and indicate that applying this assumption to electromagnetism…

Although learning about Nature of Science (NOS) promotes a variety of important outcomes, teachers often lack suitable activities for younger students to effectively address NOS. In this article I elaborate on an NOS activity developed for a teacher professionalisation workshop. The activity is suited for younger students as well, where clear…

Students' understanding of forces in circular motion is often incomplete. The problems are not limited to confusions about centripetal acceleration and centrifugal forces. This paper considers possible effects of different interventions by a teacher who has discovered the many types of free-body diagrams drawn by students for circular motion in a…

Using the layout described here (which could be photocopied or handwritten), students can see how the periodic table was first envisaged after finding similarities in the properties of common elements. Then, with more discoveries some gaps were filled and, when additional elements did not fit, new groups had to be included.

Large drop towers let you experience a couple of seconds of nearly free fall before stopping gracefully in magnetic brakes or bouncing a number of times on compressed air, as in the Turbo Drop tower considered in this work, where many complementary representations are used. An accelerometer taken along on the ride captured the forces experienced…

It is becoming increasingly important for students to go beyond engaging in design by reflecting upon the nature of engineering (NOE) and wrestling with questions such as, "What do engineers do?" and "What is engineering?" This article describes an activity in which middle school students are asked to create a product to help a…

A robust knowledge of physics entails deeply understanding electricity concepts such as conductivity and resistance. Understanding how circuits work is also critical for ensuring the safe use of electrical technology such as car batteries and downed powerlines. Curricular materials covering these content ideas are readily available for teachers.…

Huygens' principle in which every point on a propagating wave acts like a point source of radiation is a foundation principle of physics. Normally, Huygens' principle is demonstrated by passing a wave, for example a water or light wave through an aperture comparable in size to the wavelength. In this paper, an experiment is described in which a…

Is the reductionist approach to teaching chemical principles in the laboratory adequate for students to make effective evaluations? In this work, using the example of sunscreens, students first assessed the analytical chemistry parameters of the active ingredients, later comparing and contrasting them with organic chemistry information for…

Understanding thermal concepts constitutes one of the most important challenges in teaching science as these concepts are central to the principals of science and allow students to build connections among scientific disciplines. From an early age, students' interaction with daily phenomena and real situations comes to shape their conceptions of…

Newton's cradle is a well-known physics toy that is commonly used by teachers to demonstrate conservation laws in mechanics. It can also be used to investigate the physics of colliding objects, by recording motion of the balls on video film. Various experiments are described using 3-ball and 5-ball cradles, showing how different types of collision…