The Leaning Tower is a long-time staple of the demonstration room. It can be traced as far back as apparatus catalogues from the 1850s. Some years ago, while teaching himself how to use a new wood lathe, Thomas B. Greenslade, Jr. made a replica of the original design. With the top removed, the tower is stable, but once the top is added, the line…

A novel demonstration device for realizing the intuitive visual observation of the system's internal energy change is proposed. The device is safe, simple, and efficient, combining an infrared camera with a water bottle sprayer. With this setup, the changes of thermal images for air and helium during the compression and expansion processes were…

Quantitative demonstration of chemical kinetics often requires sophisticated equipment and materials. By using inexpensive and commonly available chemicals, we propose here two clock reactions, oxygen-safranin-benzoin clock and cysteine-iodine-hydrogen peroxide clock. Students simply measure and add stock solutions to start clock reactions. Sudden…

This work reports the first use of rubber latex waste as the hydrophobic reagent for a low-cost, simple, and rapid fabrication of a paper towel-based experimental device (PTED) with a circular design of 5 mm to demonstrate the factors affecting chemical equilibrium; this serves as a user-friendly means for a laboratory experiment. The illustration…

The Ball Bearing High Voltage generator is a fairly simple and transparent apparatus that can serve as a tool to motivate conceptual descriptions and calculations in electrostatics that are normally presented to our students in a rather dry and matter-of-fact fashion. For example, instead of posing a problem in the typical textbook form of…

The purpose of this paper is to present five new devices that demonstrate a variety of flow phenomena in liquids and granular materials that exhibit fluid-like behavior. These devices complement and add on to a recent collection of demonstrations that was published in this journal. The devices are self-contained and portable, and can be utilized…

The polarized optical microscope (POM) is an invaluable tool for characterizing materials such as liquid crystals and other optically anisotropic materials. Despite its frequent use in research settings, students are rarely introduced to its fundamental operation and importance. Curricula are starting to appear for applications of the POM in…

A pair of galvo mirrors reflecting light from a laser pointer is suggested for use as a school demonstration of Lissajous figures. The device is small, cheap and easy to assemble. Combined with a two-channel waveform generator, a full spectrum of excellently stable Lissajous figures can be generated (concerning frequency ratio, amplitude ratio and…

Demonstrations of physics phenomena via relatively simple devices and toys have been around for a long time. Because of the pedagogical value of demonstrations, this journal and other periodicals have published papers on the subject of classroom demonstrations including those related to fluid mechanics. Four new, low-cost apparatuses that…

This work focuses on the experimental demonstration of the hydrostatic paradox using simple tools in the form of plastic bottles and plastic syringes with a thread. For the evaluation of the results obtained the data logger Lab Quest Vernier was used. The construction of the device is presented in the first part of this paper. The second part…

In this article construction of a simple and inexpensive test card which can be used to demonstrate the polarisation ability of sunglasses is described. The card was fabricated simply by using a piece of polariser sheet with one to three layers of cellophane tape fixed on it.

We present a versatile experimental apparatus for exploring rotational motion through the interplay between the moment of inertia, torque, and rotational kinetic energy of a wheel. The heart of this experiment uses a 3D-printed wheel along with easily accessible stock components that allow for the adjustment of the moment of inertia while keeping…

I report an innovation that provides a compelling demonstration of rocket propulsion, appropriate for students of physics and other physical sciences. An electrical spark is initiated from a distance to cause the deflagration of a combustible vapor mixed with air in a lightweight plastic bottle that is consequently propelled as a rocket by the…

We have developed an online oscilloscope program which allows users to see waveforms by utilizing their computer microphones, selecting from our library of over 30 audio files, and opening any *.mp3 or *.wav file on their computers. The oscilloscope displays real-time signals against time. The oscilloscope has been calibrated so one can make…

This is the second in a series of two articles on using antique devices to teach introductory physics. As mentioned in the first article, students can more clearly see the physics required for the operation of antique devices than for modern-day technological devices. This article further discusses antiques used to teach vibrations and waves,…