We present a simple and cheap experimental setup that clearly shows how the colors of the white light spectrum after passing a prism do not recombine when emerging from an identical second prism, as it is still found in many references.

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…

A simple model of parallel motion of two point charges and the subsequent analysis of the electromagnetic field transformation invariant quantity are considered. It is shown that ignoring the coupling of electric and magnetic fields, as is done in some introductory physics books, can lead to miscalculations of the force between moving charges.…

Recently I have been investigating the frequency response of galvanometers. These are direct-current devices used to measure small currents. By using a low-frequency function generator to supply the alternating-current signal and a stopwatch smartphone app to measure the period, I was able to take data to allow a resonance curve to be drawn. This…

Consider the fall of the apple that, by legend, hit Newton on the head. Instead of using this to introduce Newton's law of gravity, we will discuss the point of view that the fall of the apple was caused by a minuscule curvature of spacetime in the region surrounding Newton and the apple tree. We will calculate this curvature using concepts and…

The peak position of the spectral density for blackbody radiation is given by the Wien displacement law. Within introductory physics materials it is often stated, or implied through example, that the color of the light emitted from a blackbody, such as the Sun, can be ascertained from knowledge of the position of that peak in the spectral density.…

With the wide availability of strong neodymium magnets, the slow and stately fall of a magnet through a conducting pipe has become a favorite classroom demo for teaching electromagnetic induction, Newton's third law, and Lenz's law. Since Lenz's law is conceptually difficult for some students, several authors have used this demo to explore in…

In this paper we describe a simple alternative to the telephone book friction experiment, a classic demonstration where a small force (generated for example by the bending of the outer pages) is amplified by the large number of surfaces in contact, resulting in a huge maximum static friction force that has to be counterbalanced in order to…

This paper examines the Torricelli law for the flow of liquid from a small drain hole in a container. It shows how the system can be modelled using either a traditional calculus-based approach or a non-calculus step-wise computer method appropriate to the background of the student group. An experiment to measure the head of out-flowing liquid as a…

Power Boxes are a new representation to provide students with a conceptual resource to analyze direct current (DC) circuits and to build conceptual understanding of energy and power use in circuits. Power Boxes are designed to provide an intermediate, conceptual step between drawing a circuit diagram and solving calculations. In this paper, we…

When a chain hangs loosely from its end points, it takes the familiar form known as the catenary. Power lines, clothes lines, and chain links are familiar examples of the catenary in everyday life. Nevertheless, the subject is conspicuously absent from current introductory physics and calculus courses. Even in upper-level physics and math courses,…

From the time of Pythagoras of Samos (sixth century BC), the Greek philosopher-scientists taught that the Earth was a sphere and the harmonies of the universe were governed by mathematical relations. With the fall of the Roman Empire in the fifth century, cultural darkness descended on Europe and all intellectual pursuits languished under the rule…

Self-regulated learning (SRL) studies have been widely researched, but there have been insufficient meta-analytical studies concerning the effects of self-regulated learning and achievement in science. This research, therefore, sought to perform a meta-analysis on the effects of self-regulated learning strategies on the achievement of students in…

In the secondary and high school science program implemented in Turkey in 2018, the importance of engineering and design skills is underlined under domain-specific skills. The purpose of this study, in which case study method, one of the qualitative research methods, is used to examine the engineering design skills of high school students within…

Many researches show that students have difficulties in understanding graphics in kinematics. Some authors argue that we can use different instructional strategies to reduce these difficulties. Based on these studies, we developed and applied a didactic sequence using educational robotics to teach graphic analysis in movements in a dimension with…