The optical spectrometer is a widely established and widely used scientific instrument for analyzing biochemical samples. However, it is expensive, bulky, and requires an external power source and a computer to operate, which makes it difficult to use in resource-limited countries and in remote locations. Advancement in smartphone technology has…

In virtual laboratories, various cognitive aids are used to improve students' performance and assist them while completing experimental tasks. However, excessive use of cognitive aids in virtual laboratories can lead to a cognitive load on students which affects their performance. In this paper, we proposed the concept of adaptive aids virtual…

The variation of the period of oscillation of a pendulum with the amplitude is known as "circular error" to clockmakers, and can easily be observed even without modern laboratory instruments. There have therefore been many approximate formulae for the pendulum period as a function of the amplitude, but the simple equation due to Denman,…

This work discusses a didactic path aimed at revisiting the first experiments on the transmission and detection of electromagnetic waves, performed by Guglielmo Marconi at the end of the 19th century. With very simple materials it is possible to set-up apparatus that allow to illustrate practically the simple physical picture of wireless…

Heart muscle cells, or cardiomyocytes, exhibit intrinsic contractility in vitro. We found that commercially-available mammalian cardiomyocytes serve as an excellent model system for studying the cytoskeleton and cellular contractility, fundamental topics in undergraduate cell and molecular biology courses. Embryonic rat cardiomyocytes were plated…

Winogradsky columns were invented by Sergei Winogradsky in the 1880s and have commonly been used as a microbiology classroom learning tool in K-12 and collegiate education. However, they can be challenging to examine with microscopy. We scaled down Winogradsky columns into nuclear magnetic resonance (NMR) tubes and replaced the natural sediment…

We outline the physics involved in the use of scanning electron microscopy (SEM) and modernise the usual textbook treatment by explaining how one can now obtain high-quality images with non-conductive specimens. As a concrete example of an application in biology, we provide several magnification series of a flea obtained using SEM.

In this paper we explain how to build a very sensitive force table using 3D-printed parts. The key component of this apparatus is a simple sensitive pulley that, together with the other components, can be printed in one day (one hour per pulley, 17 hours for a complete three-pulleys table) at the cost of 160 g of plastic filament. This force table…

Inert gas manifolds for the handling of air-sensitive materials are commonplace in the inorganic chemistry curriculum as well as in research laboratories specializing in inorganic and organometallic synthesis. Mercury bubblers are ubiquitously implemented for maintaining a positive internal pressure for air-free manifold systems, commonly known as…

The accurate and precise transport of the small amounts of the liquid by the syringe pump is widely used in many fields. In this paper, an Arduino-based syringe pump is fabricated using the computer DVD (digital versatile disc) drive. For the fabrication of the syringe pump, low-cost electronic components such as an Arduino microcontroller, a…

Physics teachers are sometimes asked to teach an astronomy course for non-majors. One can't make that class dance and sing without the starry night, but on a brightly lit campus viewing deep sky objects may seem impossible. Hence instructors often opt for planetarium shows. However: 1) Planetariums aren't the real thing. 2) People living in large…

The measurement of the charge-to-mass ratio, e/m, of the electron is a fundamental part of any study of electricity and magnetism. It is possible to use an apparatus designed to measure e/m for other things, including investigations of electron flow through a near vacuum, measuring a work function, and even exploring some quantum mechanics…

The question of how the processes around the Faraday generator with its rotating magnet should be interpreted has been controversial since its discovery by Faraday. Does the magnetic field rotate together with the rotating magnet or does it remain stationary? Furthermore, does one only need Faraday's flux law to interpret inductive processes, or…

Gel electrophoresis (GE) is the most preferred and adapted technique for the separation and identification of biological molecules like proteins/peptides and nucleic acids from diverse types of organisms. All over the world, researchers, educators, and students aspiring to work in biochemistry and molecular biology disciplines use the…

Fiber materials and textiles are topics of much research and study today, with efforts being made to produce fibers that are stronger, more durable, more breathable, and better for the environment. However, the production of fibers at the laboratory scale is uncommon and difficult past the prototype phase, and to a commercial fiber production…