Difficulties presented by students on the concept of instantaneous velocity are well known. This is in part due to instantaneous speed being often defined in terms of the notion of mathematical limit, which may not be clear to many students in introductory physics courses. In this work we present a complementary teaching proposal that can help…

We consider the operation of the hypothetical mechanical vehicle driven by an engine powered by small rockets introduced by P D Hanstead in the inaugural volume of this journal. Hanstead arrived at three contradictory conclusions regarding the change in velocity should some of the rockets malfunction at a particular time. This thought experiment…

In this paper I explain how I usually introduce the Schrödinger equation during the quantum mechanics course. My preferred method is the chronological one. Since the Schrödinger equation belongs to a special case of wave equations I start the course with introducing the wave equation. The Schrödinger equation is derived with the help of the two…

Introductory physics students often express fears regarding graphical vector addition. To ameliorate student trepidation of possibly making a mistake when moving the second vector to its new position at the head of the first vector before being added, as is most often advised by physics teachers, an alternative method is detailed here. This subtly…

Problems involving rotating systems analysed from an inertial frame, without invoking fictitious forces, is something that freshman students find difficult to understand in an introductory mechanics course. In this article we try to see what could be the factors that lead to this difficulty and propose a set of arguments that could be used to…

Many introductory astronomy courses include concepts related to basic stellar properties. In general, these are concepts that originate from the human perception of starlight. This observational aspect is not easy to incorporate in the classroom. We explore if these concepts could be developed using the built-in data in a planetarium software.…

Understanding simple electric DC circuits often represents a great challenge to many students in lower secondary schools. As a result, students' knowledge of this subject is often dominated by alternative conceptions, even after instruction. One of the reasons for these learning difficulties is the intangibility of key physical quantities and…

At the introductory level, projectile motion is usually considered under the assumption of the absence of air resistance. Even the simplest case of linear drag might be beyond the students, as it requires some familiarity with differential equations. This leaves many students wondering about the effect of air resistance on the motion and the way…

Two pendula of length "l," suspended from points separated by a horizontal distance a, can be joined in a trapezium configuration by linking the bobs with a light inextensible string of length b < a. Here we introduce this 'trapezoidal pendulum' as a charming and novel oscillatory system suitable for introductory physics laboratories.…

Students are amazed when I show them a zoo photo of an animal behind a fence and then a zoomed-in photo where the fence has disappeared. They ask 'Where did the fence go?' This paper will explore this magical phenomenon which draws from concepts in photography (angle of view, depth of field) and physics (convex lenses, focal length, real images).…

In this work we discuss the intricacies of a simulation using the MS Excel spreadsheet that allows to study in detail the process of heat transfer between two reservoirs at different temperatures through a conducting rod when heat losses are neglected. The proposed physical model computes the time dependence of the reservoir temperatures and…

In this article, we outline a demonstration that is relatively simple to perform but whose results require a quite subtle interpretation of Faraday's Law. When a very small magnet is dropped through a coil it can tumble as it falls leading to 'spikes' in the measured emf signal. The experiment, and demonstration, can be used in an introductory…

Costume jewelry beads are employed to demonstrate how a beam of beads are able to transform into a simple pendulum (single bead) where the pendulum length remains constant throughout. These beads are common and inexpensive for instructors, as well as attractive and exciting for students. Beads are removed from the top, keeping the same pendulum…

This article considers a further experimental demonstration of the equations of projectile motion employing the popular video-based motion modeling tool called Tracker. Using a downloaded video--of a free throw attempt by the NBA star Lebron James--from YouTube.com, the primary equations of projectile motion, together with a number of projectile…

A lab activity for teaching physics students the fundamentals of statistical analysis during the first few weeks of instruction is described. This activity involves students timing a pulse of light generated by an Arduino device of fixed duration with individual timers (e.g. stopwatch, iPhone timer). To select the most precise timing methods and…