Reviews analogies used to try to capture the concept of the magnitude of Avogadro's number, including analogies related to small/tiny objects, counting, people, water, and money. Also presents several new ones which are based on modern computers and printers. (JN)

Prolog is one of the most successful "very high level languages." Describes this programming language (a product of artificial intelligence research) and attempts to show how it functions by using some short examples to illustrate its essential features. (JN)

The unit basis approach to problem solving analyzes a question in such a way that the student clearly sees what data are needed to solve the problem. Two examples are presented to illustrate the approach. (JN)

Presents a new method of uncertainty propagation which concentrates on the calculation of upper and lower limits (the "worst cases"), bypassing absolute and relative uncertainties. Includes advantages of this method and its use in freshmen laboratories, advantages of the traditional method, and a numerical example done by both methods.…

Recent developments in molecular biology and new interpretations of the fossil record are gradually altering and adding to Charles Darwin's theory, which has been the standard view of the process of evolution for 40 years. Several of these developments and interpretations are identified and discussed. (JN)

Discusses various aspects of fly casting to illuminate the physics of fishing. They include examining whether the bending of the rod propels the fly as a bow propels an arrow and determining how an angler resists the pull of a hooked fish while reeling it in. (JN)

Although many textbooks include a description of simultaneous determinations employing absorption spectrophotometry and treat the mathematics necessary for analytical quantitations, treatment of analytical wavelength selection has been mostly qualitative. Therefore, a general method for selecting wavelengths for optimum precision in simultaneous…

Relations between structure and function of the Golgi apparatus are emerging from recent laboratory work on this cellular organelle which modifies proteins, sorts them, and packages them for delivery. The structure's three specialized compartments are explained through discussions of the glycosylation pathway, density-gradient experiments,…

Since Project SERAPHIM personnel could not keep in contact using traditional methods of communication, a computer conference called CHYMNET was developed. A description of CHYMNET (which uses Confer, a commercially available program on mainframe computers running the Michigan Terminal Service) is provided. (JN)

Hot spots are isolated areas of geologic activity where volcanic eruptions, earthquakes, and upwelling currents occur far from plate boundaries. These mantle plumes are relatively stable and crustal plates drift over them. The nature and location of hot spots (with particular attention to the Hawaiian Islands and Iceland) are discussed. (DH)

The cause of the Cretaceous/Tertiary extinction has become a major geologic controversy. Current evidence for the two opposing views is reviewed to provide an introduction to the controversy and to form the basis for a seminar of discussion topic. (Author/JN)

Presents a simple example that illustrates various aspects of the Rayleigh-Schrodinger perturbation theory. The example is a particularly good one because it is straightforward and can be compared with both the exact solution and with experimental data. (JN)

The concept of operators plays a vital role in formulating the basic principles of quantum mechanics. However, the selection of a particular operator in textbooks may seem arbitrary to students. Therefore, a theorem is presented which provides the necessary guideline for the choice of ladder operators. (JN)

Discussion of crystalline solids in undergraduate curricula often includes the use of radius ratio rules as a method for predicting which type of crystal structure is likely to be adopted by a given ionic compound. Examines this topic, establishing more definitive guidelines for the use and reliability of the rules. (JN)

The establishment of a universal chemistry network is recommended. Lists: (1) some of the possible applications for the network; (2) ideal characteristics of such a network; and (3) available options and how they fit the ideal characteristics. (JN)