The article describes a methodology for studying Fresnel diffraction with the active involvement of students in discussing the results of a demonstration experiment. To create a clearly visible model of Fresnel zones, a centimeter radio wave range was chosen, in which the first zone is about 10 cm in size. This makes visible the created…

The udu is a traditional Nigerian percussion instrument that can be thought of as a Helmholtz resonator with two apertures. We use a simple two-particle mechanical analogue to study the behaviour of such a resonator and find that the model describes quite well the main features of udu acoustics.

We present a simple activity based on the liquid-drop model which allows secondary school students to explore the uses of mathematical models and gain an intuitive understanding of the concept of binding energy, and in particular the significance of positive binding energy. Using spreadsheets provided as supplementary material, students can…

Simple energy balance models of planetary systems are of fundamental importance to understanding equilibrium temperatures. Most textbooks that discuss energy balance take a further step and include the effects of an atmosphere on the surface temperature. It is noticeable, however, that in such discussions of planetary surface energy balance some…

In this article, we propose a simple and accessible model of a magnetic levitator fitted with a Hall sensor. This model also allows to determine the magnitude of the magnetic field within the levitator working volume. Students can also compare the experimental magnetic field values to reference values in magnetism textbooks. This Arduino-based…

It is often necessary to enrich the teaching environment in order for students to learn optics in depth and to interpret the real optical situations with the information they have learned. In this study, a virtual teaching environment was developed using by Algodoo, a 2D simulation software. An eye model was created in order to explain the…

In recent years, general relativity (GR) and gravitational-wave astronomy have emerged both as active fields of research and as popular topics in physics classrooms. Teachers can choose from an increasing number of modern instructional models to introduce students to relativistic ideas. However, the true potential of an instructional model can…

This paper shows how two distinct but related models can be used to bring out the essential physics of heat flow in one dimension. The first is a simple step-wise procedure using "SMath Studio," while the second is an electric analogue using a basic RC ladder connected to an Arduino microcontroller. Both models can be demonstrated in…

A quantitative experiment where we measure the acceleration of spheres of radius "R" rolling on an inclined U-shaped profile of width "2D" is presented. For a given inclination, we examine the behaviour of four solid spheres having different diameters; in contrast to what is usually assumed to be the case, the experimental…

In order to increase understanding of the cochlea and to illustrate its connection to basic physics, a functional model was developed. It was found to be useful in exploring the basic dynamics of the basilar membrane and its role in the frequency mapping of the cochlea.

A glass of water covered with a disk with a hole in it can be turned upside down without spilling the water in the glass, provided the hole is small enough and the disk is pressed against the rim of the glass. A quasistatic numerical simulation based on hydrostatic pressure and surface tension of water was used calculate the critical hole diameter…

In this paper, we present a physical modeling activity whose objective is to allow students to determine the differences between a disk and a sphere using pure scientific criteria. Thereunto, we reproduce the Sun-Earth-Moon system with low-cost materials and compare the illumination effects on the Moon considering two possible shapes for it (a…

A video of darkening scenery during the 15 min prior to totality of the 21 August 2017 total solar eclipse is presented and discussed. The luminances of the scenes at 1 min intervals are obtained by averaging pixel data of stills from the video. The experimental results are compared to the theoretical model of uniform radiance from the exposed…

We propose an experimental activity in order to develop a mathematical model that relates step length and walking speed of human beings. We employ two well-known physics teaching softwares, namely, Tracker to carry out the video analysis and LibreOffice/Calc to obtain graphs, trend lines and equations. The predictions of our model are compared…

In a spiral galaxy, the stars move in a circular motion around the galactic center, and the relation between velocity and the orbital radius is referred to as the rotation curve. Previous astronomical observation data indicate that the rotation curve is flat at the periphery of the galaxy, which completely dissatisfies Keplerian decline. Assuming…