A simple photometric device was built to measure the kinetics of the title reaction. The device consisted of a green light-emitting diode (centered at 520 nm), a sample vial, a photodiode, and an Arduino microcontroller board. These parts were mounted on a black poly(lactic acid) holder which was manufactured by utilizing three-dimensional…

In this study, we describe a method to employ a conventional compound light microscope, usually available in laboratories, to obtain fluorescence. In particular, two pieces of colored acrylic plastic were utilized to assist the microscope in filter performance. We also attempted to examine the applicability of the setup by staining onion cells…

Diffraction is an important phenomenon in physics. This paper describes using a scanning electron microscope (SEM) to produce cross-sectional images of iridescent seashells. When seashell cross-sections are viewed in a SEM, regular structure is seen. Seashells are a good example of a biocomposite material and good natural objects for introducing…

This paper demonstrates the use of a smartphone as a low-cost multi-channel optical fibre spectrophotometer suitable for physics laboratory classes. A custom-designed cradle and structure support were fabricated using 3D printing. The plastic optical fibres were arranged and inserted into the hole of the cradle to guide the light to the rear…

STEM is about the integration of science, technology, engineering and mathematics. To teach STEM effectively, students need practical examples of subject integration. A good example is the use of an electron microscope in teaching physics and biology. An electron microscope is an instrument in which the operation depends on electromagnetism and…

Laboratory experiments provide students a tangible means of understanding dry, abstract concepts. A simple and engaging introductory wet chemistry laboratory has been developed relating quantum mechanics to color, which has been implemented for a class of about 600 students per academic year for over three years at Brown University. Color is an…

Although research and new technologies have introduced different ways of observing microorganisms, including scanning and electron microscopy, these methods are expensive and require equipment that is typically not found in a middle school classroom. The transmission-through-dye technique (TTD; Gregg et al., 2010), a new optical microscopy method…

A simple photometric assembly based in an LED as a light source and a photodiode as a detector is proposed in order to follow the absorbance changes as a function of the titrant volume added during the course of acid-base titrations in the presence of a suitable visual indicator. The simplicity and low cost of the electronic device allow the…

To overcome students' inaccurate prior knowledge on primary additive colours, a coloured-light mixer has been constructed to enable students to observe directly the colours produced and reach the conclusion by themselves that the three primary colours of light are red, green, and blue (NOT red, yellow, and blue). Three closely packed tiny…

A new type of DVD spectroscope, the periscope type, is described and the numerical analysis of the observed emission and absorption spectra is demonstrated. A small and thin mirror is put inside and an eighth part of a DVD is used as a grating. Using this improved DVD spectroscope, one can observe and photograph visible spectra more easily and…

This investigation was part of a multi-lesson unit that gave students direct experience using increasingly sophisticated tools to make more detailed observations and measurements of light. Through these lessons, students experienced a key aspect of the nature of science (McComas 2004), namely how scientists constantly refine and modify theories as…

In this article, we present an overview of a suite of light and spectroscopy education materials developed as part of Project LITE (Light Inquiry Through Experiments). We also present an analysis of how introductory college astronomy students using these Project LITE materials performed on the Light and Spectroscopy Concept Inventory (LSCI)…

Two different methods of measuring the temperature of an incandescent lamp at various voltage levels are described. By observing the color produced at a particular voltage levels, the lamp's color as a function of temperature can be determined. Needed equipment include a variac, a voltmeter, and an ammeter. (KR)

Traces the development of instruments used in spectrophotometry. Discusses how spectrophotometric measurements are made. Describes the color comparator, the filter photometer, and the spectrophotometer. Outlines the evolution of optical systems, including light sources, the monochromator, the photodetector, double-beam optics, and split-beam…

This military-developed text contains four volumes of materials for use in training apprentice still photography specialists. Covered in the individual volumes are the following topics: general subjects (safety and environmental protection); still photographic fundamentals (sensitized black and white film materials, photographic exposure, still…