Gravity bends light. One can argue this by reasoning that a beam of light should travel in a curved path when viewed from within an accelerating frame of reference, and then invoking Einstein's principle of equivalence, which asserts that the effects observed in an accelerating frame of reference are indistinguishable from the effects observed in…

This study aims to investigate the effect of the teaching model developed for hot conceptual change on middle school 7th-grade students' understanding of the Nature of Science (NOS) aspects. In this qualitative and exploratory study, activities were carried out with 24 students of two classes in a village school in the South Marmara region using a…

The objective of this second part of the work is to present heuristic derivations of the three classical tests of general relativity. These derivations are based on the Einstein equivalence principle and use Newtonian physics as a theoretical framework. The results obtained are close to Einstein's original predictions. Historical and anecdotal…

In many introductory physics classes, diffraction of light is introduced first, then more advanced diffraction topics such as x-ray diffraction, Bragg's law, and crystallography are covered. Since using x-rays raises safety concerns and atomic spacing in a crystal is not easy to change, microwaves with macroscopic crystals have been used to study…

The concept of black body is of primary importance in studying the energy transfer of thermal electromagnetic radiation at all wavelengths. Several physical bodies like incandescent lamps, electric heaters, stoves, the sun and the other stars, microwave background radiation, etc., are considered to be black bodies as their radiation spectra fits…

Malus's law states that the intensity of light after passing through two polarizers is proportional to the square of the cosine of the angle between the polarizers. We present a simple setup demonstrating this law. The novelty of our work is that we use a multi-turn potentiometer mechanically linked to one of the polarizers to measure the…

The smartphone's ambient light sensor has been used in the literature to study different physical phenomena. For instance, Malus's law, which involves the polarized light, has been verified by using simultaneously the orientation and light sensors of a smartphone. The illuminance of point light sources has been characterized also using the light…

Quantum physics challenges our views of the physical world and describes phenomena that cannot be directly observed. The use of language is hence essential in the teaching of quantum physics. With a sociocultural view of learning, we investigate characteristics of preuniversity students' small-group discussions and their potential for enhancing…

A simple diffraction experiment was designed using banana stem as natural grating. Coherent beams of lasers with wavelengths of 632.8 nm and 532 nm that pass through banana stem produce periodic diffraction patterns on a screen. The diffraction experiments were able to measure the distances between the slit of the banana stem, i.e. d = (28.76 ±…

Understanding reflection and refraction are an integral part of school and college learning. In nature even birds and fish (Archer fish) very skillfully use refraction to strike down prey present above or below the water surface. Fermat's principle allows one to look beyond the reasons behind the laws governing the reflection and refraction. A…

Quantum physics describes light as having both particle and wave properties; however, there is no consensus about how to interpret this duality on an ontological level. This article explores how pre-university physics students, while working with learning material focusing on historical-philosophical aspects of quantum physics, interpreted the…

Exothermic reactions can present safety hazards and there is a recognized need for reaction safety education at the undergraduate level. We present an experiment that illustrates the pitfall of direct scale-up of an exothermic reaction that can lead to thermal runaway. The iodide-catalyzed hydrogen peroxide decomposition reaction yields…

Young's double-slit experiment is one of the most historically significant works in physics, and one that is easily done in an introductory physics class. It is also an excellent example of an investigation that allows us to infer the nature of phenomena beyond direct observation. Unfortunately, perhaps because of this, it is often also an…

Lens imaging is a classic topic in physics education. To guide students from their holistic viewpoint to the scientists' analytic viewpoint, an image-based approach to lens imaging has recently been proposed. To study the effect of the image-based approach on undergraduate students' ideas, teaching experiments are performed and evaluated using…

The Einstein-First project approaches the teaching of Einsteinian physics through the use of physical models and analogies. This paper presents an approach to the teaching of quantum physics which begins by emphasising the particle-nature of light through the use of toy projectiles to represent photons. This allows key concepts including the…