On April 14, 1912, the British passenger liner R.M.S. "Titanic" struck an iceberg. The ship sank in a fraction of the time designers had estimated following a worst case scenario. The purpose of this article is to examine the atmospheric refractive phenomena that might have played a significant role in obscuring the iceberg from…

The movement of air into and out of the lungs is facilitated by changes in pressure within the thoracic cavity relative to atmospheric pressure, as well as the resistance encountered by airways. In this process, the movement of air into and out of the lungs is driven by pressure gradients established by changes in lung volume and intra-alveolar…

A 2.7 m long stringless pendulum was set up to measure the coefficient of rolling friction of various balls, at higher rolling speeds than usually observed with a short stringless pendulum. The arrangement is easy to set up and makes an impressive classroom demonstration as well as an interesting laboratory experiment.

Collective motion in living matter is highly intriguing but can also be observed in charged colloidal systems. Collective motion observed in colloidal systems requires extensive material synthesis, external stimuli, and advanced characterization methods that might be highly costly to be employed for teaching. Besides that, colloidal systems can…

Resonance is a widely observed physical phenomenon, occurring when an oscillator experiences a driving force whose frequency closely matches one of its own natural frequencies. Due to its broad applicability in physics, resonance is a familiar topic in the physics teaching literature. Previous studies include resonant energy transfer between…

Races between moving objects are an engaging way to teach dynamics to introductory physics students. One standard example consists in racing hollow and solid cylinders as they roll down an inclined plane. Another striking demonstration is a race between two marbles on side-by-side tracks that start and end together, but with one track taking a…

A hula hoop rotating around a person's waist is an example of circular motion where the centripetal force on the hoop is directed towards the centre of the circle rather than the centre of the hoop. The friction force on the hoop is relatively small by comparison since the hoop rolls around the waist. A slight complication is that the hoop rotates…

The Cartesian diver is an old and useful demonstration of fluid-related phenomena, including Archimedes' and Pascal's principles. While the diver gets its name from the scientist and philosopher René Descartes, the first written description of the device was given by Raffaello Magiotti. The modified diver presented here is related to Feynman's…

This study explored the impact of interactive e-books on the viewing behaviors of children in science demonstrations at museums. To conduct this study, an interactive e-book on a pendulum experiment was developed and integrated into a physical science demonstration at a museum. Two scientific demonstrations were conducted in this study. The first…

The flow of air around a baseball and over the seam acts to slow the ball and to deflect it sideways. Turbulent flow can be visualized, and sideways deflection of the ball can be observed clearly if the ball is dropped in a glass fish tank and filmed with a high-speed camera. Results are presented for a baseball and also for a billiard ball with a…

Teaching through discrepant event activities increases student interest in science. In this article, I will introduce a well-known 19th century demonstration, the Tissandier experiment, to stimulate curiosity among students learning the concept of inertia. In this demonstration, a hard object (e.g. a wooden rod) placed on fragile supports is…

It can be a challenge to come up with simple demonstrations of circular motion and conservation of energy. One such demonstration consists of a large exercise ball, off of which a small solid ball is rolled. The small ball is coated in finger paint so, after an initial push, it rolls nearly without slipping and creates a visible track.

Newton's cradle is often discussed in science classrooms as a clear example of the laws of conservation of momentum and energy although it has been shown that this use is somewhat misleading. Approaches to understanding the behaviour of this apparatus are often over-simplified and deficient or over-complex and with little impact among teachers. In…

Using Tracker, a popular video-based physics modeling tool, the position-time data of magnetically damped oscillations of a simple pendulum are acquired. Eddy currents are generated on an aluminum sheet as the magnetic pendulum bob passes over it and the induced magnetic field opposes that of the magnetic bob. This causes the damping. A…

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…