Students of physiology are taught that the body's homeostatic mechanisms are in place to maintain the body's internal environment. This is most often associated with maintaining health. Congestive Heart Failure represents a disease in which the body's homeostatic mechanisms worsen the progression of the disease. Using the analogy of Santa Claus…

It can readily be demonstrated that when a low frequency alternating voltage is applied to an iron-core coil the impedance is much higher than the direct current resistance of the coil. To understand how the high level of impedance arises it is necessary to explain how magnetic and electrical induction give rise to a current in the coil that…

We propose the use of a laptop with a program generator and a transistor power amplifier to control the frequency, duration and amplitude of the LED stroboscope flashes. Examples of the stroboscopic photographs are given.

The conical pendulum provides a rich source of theoretical and computational analysis and the present work presents a seamless continuation of the previous publication. The tension force F[subscript T] and centripetal force F[subscript C] are explored further in linearization analyses and the appropriate slopes are explained. A similar analysis is…

The transformations of electric and magnetic fields are usually introduced by viewing systems such as a long, straight current-carrying wire and a parallel plate capacitor in two different reference frames. These well-known examples show that magnetism is a necessary consequence of augmenting electrostatics with relativity. Because they require…

All teachers know that the opening few minutes of any lesson can be the critical part. It is the chance to set the scene, to establish order and sense of purpose, to enthuse and grab attention and perhaps to establish boundaries. It launches the learning. Bob Kibble discusses ways of setting out the shape and direction of lessons without using a…

Many science educators have been incorporating the use of case studies into their teaching. An advantage of using minicase studies is that they can be used at any time throughout the semester to reinforce important topics covered without having to sacrifice a large amount of class time. In this article, the authors present a series of 10 mini-case…

Torsional effects influence kinetic selectivity in a wide range of organic transformations. As such, textbooks commonly use Newman projections to illustrate the torsional effects that arise in their transition states. Unfortunately, these representations fall short when the reaction occurs "within a ring." In many cases, the torsional…

This teaching brief describes an engaging, in-class exercise that introduces genetic algorithms as well as advanced Excel functions and capabilities by modeling the familiar Sudoku puzzle. Student groups are first asked to manually solve a given puzzle and then translate that solution methodology to a spreadsheet model. This exercise can be used…

Many teachers have had students ask the proverbial question, "When will I ever use this in my life?" In the sciences, especially physics, teachers seem to battle this torrent of indifference continually. Although many areas of our students' lives can distract them from their academic pursuits, we as teachers must be introspective in…

Developing simpler, more accessible, and more affordable methods for the determination of the boiling point of microscale amounts of liquid may lead to increased utilization in research and teaching laboratories as an analytical technique. Our efforts toward that goal have revealed that digital hot plates can be used as the heat source. One option…

Popular demonstrations commonly use stretched spandex fabric to illustrate the way in which curved spacetime mimics the force of gravity in general relativity. There are significant potential conceptual pitfalls to such an approach. In particular, it obscures the fact that most of what we ordinarily feel as gravity is due to the warping of time…

This work outlines the inadequacies of the "ions in a sea of electrons" model. Some general properties of metals are stated. A different "soft/flexible" sphere model is described. The benefits of using this other model to account for metallic properties are discussed. Equations based on the soft sphere model are used to…

An understanding of buffers is important in a variety of chemistry subdisciplines, with relevant applications to the life sciences and health profession-related fields. Here, we describe the development and implementation of a lab that involves creating a buffer solution using baby wipes and deionized water. The goal of this lab was to emphasize a…

The students in our physical chemistry course pointed out an interesting trend in the bond dissociation energies (BDEs) of successive homolytic cleavages of hydrogens from methane and water. Namely, while there is an increase in BDE from CH[subscript 4] to CH[subscript 3], there is a decrease in BDE from H[subscript 2]O to OH. In order to explain…