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The conduction of electricity is an important topic for any basic physics course. Issues of safety often results in teacher demonstration experiments in front of the class or in extremely simple though--for students--not really fascinating (not to say boring) hands on activities for everybody using 1.5 V batteries, cables and light bulbs etc. Here we briefly review some basic facts about conduction of electricity through the human body and report a simple, safe, and awe inspiring electrical conduction experiment which can be performed with little preparation by a teacher involving the whole class of say 20 students.

Presents a study that examined the photoelectrical and optical properties of molecular beam epitaxy growth of Pb[sub1-x]Eu[subx]Se. Details on the experiment; Results of the study; Conclusions.

Proposes a semiempirical model that correlates the broadening of the absorption edge with both transitions below the energy gap and with transitions by the Kane band model. Information on (Hg,Cd)Te; Mechanisms that contribute to the broadening of the absorption edge; Potential causes of the permanent broadening of the absorption edge; Difference between the Urbach tail and the square-root region.

Infrared spectrometry is one of the most important tools in the field of spectroscopic analysis. This is due to the high information content of spectra in the so-called spectroscopic fingerprint region, which enables measurement not only of gases, but also of liquids and solids. Today, infrared spectroscopy is almost completely dominated by Fourier transform infrared (FTIR) spectroscopy. FTIR spectroscopy is able to detect minute quantities in the ppm and ppb ranges, and the respective analyses are now standard tools in science as well as industry. Therefore FTIR spectroscopy should be taught within the standard curriculum at university to physicists and engineers. Here we present respective undergraduate laboratory experiments designed for students at the end of their third year. Experiments deal first with understanding the spectrometer and second with recording and analysing spectra. On the one hand, transmission spectra of gases are treated which relate to environmental analytics (being probably the most prominent and well-known examples), and on the other hand, the focus is on the transmission and reflection spectra of solids. In particular, silicon wafers are studied-as is regularly done in the microelectronics industry-in order to characterize their thickness, oxygen content and phonon modes. [ABSTRACT FROM AUTHOR]

The content of a student lab course is described which deals with characterization of the most important parameters governing the performance of infrared cameras. In detail, the parameters describing the temperature resolution, spatial resolution and time resolution of commercial IR cameras are analysed using simple lab experiments. Understanding the respective performance of the system is the prerequisite for applying infrared thermal imaging to quantitative measurements in physics and technology. [ABSTRACT FROM AUTHOR]

Reflections from glass fronts of curved shape buildings are discussed. Irradiance within the respective caustics can become quite large with regard to regular sun irradiance and can lead to thermal effects. These may cause problems as has been reported for some existing buildings. The phenomena are theoretically discussed for a variety of systems made of segments of cylindrical mirrors using ray tracing models. In particular, six parameters are varied which have an influence on the caustic: building height, building width, radius of curvature, building orientation as well as sun elevation and azimuth angles. In addition, experiments have been performed for various curved shape mirrors and smallscale models of an existing building, for which problems are known to exist. In particular, we investigated the resulting caustic forms visually as well as with infrared cameras to visualize respective thermal effects. Results can explain all features of reported problems. Providing a link to everyday life and modern architecture, the topic is suitable for introducing mirror optics experimentally at school and undergraduate aswell as theoretically at undergraduate and graduate level. [ABSTRACT FROM AUTHOR]

The article describes how an improvised interferometer can be built using a kitchen table, modeling clay, glass plates, and mirrors. According to the author, while interferometer setups have been used in colleges and universities, high schools have rarely used them due to their complex assemblies and expensiveness. The author describes how several interferometers, for example a Jamin, a Micheson, or a Mach-Zehnder, can be built from common household components.

Double pane windows are common objects which can enrich physics teaching at undergraduate level at least in five different fields. First, having sealed inner spaces filled with gas, one can discuss gas law problems upon changes of pressure and/or temperature. Second, when discussing temperature differences between inside and outside, one needs to take into account the associated heat transfer mechanisms which define the pane temperatures, enclosing the gas. Third, using elastic properties of the glass, one may treat deformations of the window panes upon those changes or additional manually applied external pressure. Fourth, the reflective properties of glass combined with the pane deformations result in concave or convex mirrors, which when illuminated by the Sun, may lead to focal points on projection areas such as facing houses. Fifth, such areas receive an increased irradiance which leads to associated thermal effects. Starting from the most obvious daily life phenomenon, the fascinating caustics of reflected sunlight on streets or walls, all of these double pane window phenomena are investigated experimentally as well as theoretically. [ABSTRACT FROM AUTHOR]