This US study investigates interactive associations between structure in inquiry-type learning activities and academic attainment in high school science with introductory college science performance as the outcome. Past studies of this type have tended to use smaller samples and shorter-range methods of assessing the influence of interactions.…

A guided-inquiry exercise conducted in both the lecture and laboratory components of a college introductory chemistry course for non-science majors is described. The exercise gave students the opportunity to independently determine the relationship between the temperature of water in an aluminum soda can and the intensity of implosion upon placing…

Studies from our laboratories over recent years have uncovered the existence, and established the properties of a variety of mitochondrial transporters. The properties of these transporters throw light on a variety of biochemical phenomena that were previously poorly understood. In particular the role of mitochondrial transport in energy…

One of the most fun demonstrations in a freshman mechanics class is the levitation of a ball in a steady air stream even when the jet is directed at an angle. This and other demonstrations are often used to argue for the validity of Bernoulli's principle. As cautioned by some authors, however, it is important to avoid making sweeping statements…

The physics curriculum at all educational levels can be enriched to include tools for strengthening students' information evaluation skills. The "Report of the Joint APS-AAPT Task Force on Graduate Education in Physics" calls for such training to be part of graduate programs, but training to acquire these lifetime skills can be incorporated in the…

Most physics instructors are motivated by a genuine interest in their subject area and in using physics to understand real-world phenomena. While many premedical students may share these interests, most are motivated by fulfilling their degree requirements and gaining admittance into medical school. To achieve this latter goal, they need excellent…

In this paper, we take a look at two electrostatics problems concerning hemispheres. The first problem concerns the direction of the electric field on the flat cap of a uniformly charged hemisphere. We show that the symmetry and principle of superposition coupled with Gauss's law gives a delightfully simple solution and then go on to examine how…

The article presents the way in which freeware Internet programs can be applied to teach [superscript 1]H NMR spectroscopy. The computer programs described in this article are part of the educational curriculum that explores spectroscopy and spectra interpretation. (Contains 6 figures.)

We develop a fundamental principle depicting the generalized ray formulation of optics provided by the Wigner function. This principle is formally identical to the Huygens-Fresnel principle but in terms of opposite concepts, rays instead of waves, and incoherent superpositions instead of coherent ones. This ray picture naturally includes…

We study a particle sliding on a rough inclined plane as an example of a mechanical problem with nonholonomic constraint. The particle is launched in an arbitrary direction so that its motion has both a horizontal and a "vertical" (i.e., up- and downhill) direction. The friction force acts along the instantaneous velocity, so that the horizontal…

In this work, we present a simple analysis of binary diffraction gratings with different slit widths relative to the grating period. The analysis is based on a simple phasor technique directly derived from the Huygens principle. By introducing a slit phasor and a grating phasor, the intensity of the diffracted orders and the grating's resolving…

The construction of combined plastic membrane electrode for hydralazinium cation from a disposed glass electrode is described. A variety of electrodes could be prepared by students using other types of polymers, plasticizers, or exchangers which could also help to study effects of pH and temperature, or environmental investigations.

Various water-alcohol and alcohol-alcohol based experiments are used to demonstrate how the quartz-crystal microbalance (QCM) technique is used for measuring the viscosity of a system. The technique is very advantageous, as it is inexpensive and provides digital output.

For more than 200 years, the beautiful "molybdenum blue solutions" have been a puzzle for chemists because they could not determine the molecular structures of the solutes while experiments showing the Tyndall effect proved the presence of "giant species". This problem was finally solved in Bielefeld. As a result of this discovery, novel inorganic…

A lab practical exam for second-year organic chemistry is presented that tests multiple lab skills and theory that the students have acquired directly from laboratory experiences. This exam motivates students to learn lab skills and is an effective end-of-term test for many of those skills. (Contains 2 figures.)