This paper describes an experimental investigation of the skin depth effect for electromagnetic waves in salt water using a cell phone that is immersed to a critical depth where it no longer responds when called. We show that this critical depth is directly proportional to the theoretical skin depth for a range of salt concentrations.

After many years of confusion, thermal performance of sleeping bags has now been quantified and unified using expensive test techniques. Based on Newton's law of cooling, we present a simple inexpensive test and model to check manufacturers' claims on the temperature performance of a range of modern sleeping bags.

Understanding Physics is a great end in itself, but is also crucial to keep pace with developments in modern technology. Wireless power transfer, known to many only as a means to charge electric toothbrushes, will soon be commonplace in charging phones, electric cars and implanted medical devices. This article outlines how to produce and use a…

Understanding how to perform an enzyme assay is a critical learning skill in the undergraduate biochemistry curriculum. Students in biochemistry typically have been exposed to the use of NMR spectroscopy as a tool to determine chemical structure, but rarely are they exposed to the utility of NMR to evaluate enzyme kinetics. Furthermore, coverage…

Science teachers' beliefs about teaching and learning are a vital component of teachers' professional competence and are often assumed to impact classroom practice. To date, these beliefs have been predominantly investigated regarding teaching and learning in general or for a particular science subject (e.g., physics). It remains to be determined…

We described a simple method for detection of Fe on a thread-based analytical device. Fe reacts with 1,10-phenanthroline to form a colored band on a cotton thread; the length was measured to quantify the contents of Fe using a ruler. This method has the advantages of easy operation, low cost, easy fabrication, and reduced sample/reagent…

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…

Undergraduate research is a valuable tool to demonstrate both the dedication and time required to be a successful biologist. One area of research that has intrigued students over the last several years is cytotoxicity. However, at smaller undergraduate institutions, the time, training, and funding available for these research studies may be…

How to improve students' understanding of energy transformation and conservation remains one of the main challenges of energy teaching. To address this challenge, we developed a new teaching strategy suited to high school based on history and philosophy of science (HPS). It involves five key ingredients: study and reproduction of Joule's…

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…

The implementation of an integrated approach to upper-level undergraduate chemistry laboratory instruction that incorporates student choice both in the selection and sequencing of the experimental work is presented. The approach involves combining laboratory work in several traditional subdisciplinary areas of chemistry in a single course.…

In order to introduce the concept of covalent organic frameworks (COFs), an important class of predictable crystalline porous polymers, an integrated laboratory experiment for advanced organic chemistry students is reported. The importance of these kind of polymers and their multiple applications are presented as a part of key concepts in polymer…

The introduction of the Wireless Smart Cart by PASCO scientific in April 2016 has ushered in a paradigm shift in the design and implementation of low-cost undergraduate physics and engineering laboratory experiments. The use of smartphones in experimental physics is by now widely accepted and documented. The smart cart in combination with…

An experiment for the undergraduate organic chemistry laboratory involving a method for the isolation of eugenol from cloves has been developed. The experiment employs microwave-assisted extraction (MAE) of the essential oil from whole cloves using aqueous ethanol and the subsequent isolation of eugenol by acid-base extraction. The MAE allows for…

Melanoma, a type of cancer that develops in melanocytes, is usually caused by direct exposure of skin to ultraviolet (UV) radiation resulting in cellular damage. In this study, a procedure to determine the effects of various commercial sunscreens with SPF values ranging from 15 to 100 was developed using pig skin to mimic human skin. These…