Based on our novel method recently published in the "Am. J. Phys." 77 337-43 (2009) for finding precise values of the indices of refraction for dielectrics from measurements of the polarized light reflected by the surface, in this paper we propose an improved technique for finding Brewster angles with a better precision, of 0.001 degrees, using…

Extracting DNA from fruit and vegetables provides students with hands-on opportunities to engage with a visualisation of genetic material that can later be supported by ICT and practical model making. Here is a quick, cheap and easy way to extract DNA from strawberries that avoids the mess involved in other DNA extractions, such as from dried…

We describe a simple, low-cost laboratory session to demonstrate the Fahraeus-Lindqvist effect, a microphase flow phenomenon that occurs in small blood vessels and alters the effective rheological properties of blood. The experiments are performed by flowing cells through microchannels fabricated by soft lithography and characterization of cell…

This study was conducted to examine the results of using a low-cost hands-on setup in combination with accompanying activities to promote understanding of the contact mode of atomic force microscopy (AFM). This contact mode setup enabled learners to study how AFM works by hand scanning using probing cantilevers with different characteristics on…

Hairy root transformation has been widely adapted in plant laboratories to rapidly generate transgenic roots for biochemical and molecular analysis. We present hairy root transformations as a versatile and adaptable model system for a wide variety of undergraduate laboratory courses and research. This technique is easy, efficient, and fast making…

A simple experiment to reveal the dimension of the pore space in sponges is proposed. This experiment is suitable for the first year of a physics or engineering course. The calculated dimension of the void space in a sponge of density 16 mg cm[superscript -3] was 2.948 [plus or minus] 0.008. (Contains 2 figures.)

Using macroscopic thermodynamics, the general law for adiabatic processes carried out by an ideal gas was studied. It was shown that the process reversibility is characterized by the adiabatic reversibility coefficient r, in the range 0 [less than or equal] r [less than or equal] 1 for expansions and r [greater than or equal] 1 for compressions.…

The problem of obtaining the apparent equation of motion and shape of a moving body from its arbitrary given equation of motion in special relativity is considered. Also the inverse problem of obtaining the body's equation of motion from a known equation of motion of its image is discussed. Some examples of this problem solution are considered. As…

Two compounds, K[subscript 2][Cu(C[subscript 2]O[subscript 4])[subscript 2]] times 4H[subscript 2]O, 1, and K[subscript 2][Cu(C[subscript 2]O[subscript 4])[subscript 2]] times 2H[subscript 2]O, 2, were synthesized under controlled conditions. By controlling the concentration of the reaction solutions, it is possible to isolate a kinetic product 1…

The Millikan oil drop experiment has been characterized as one of the "most beautiful" physics experiments of all time and, certainly, as one of the most frustrating of all the exercises in the undergraduate physics laboratory. A literature review reveals that work done on addressing student difficulties in performing the oil drop experiment has,…

A unique, interdisciplinary collaboration between chemistry and classics has led to the development of an experiment for nonscience majors. This instrumental analysis experiment was designed for use in an archaeology course to quantify the amount of lead in ancient bronze coins. The coins were corroded beyond visual identification, so provenance…

A discovery-based nucleophilic substitution experiment is described in which students compare the reactivity of chloride and iodide ions in an S[subscript N]2 reaction. This experiment improves upon the well-known "Competing Nucleophiles" experiment in that it does not involve the generation of hydrogen halide gas. The experiment also introduces…

A single-pot procedure for the preparation of methyl salicylate (oil of wintergreen) from commercial aspirin tablets has been developed. The synthesis proceeds via a tandem transesterification-Fischer esterification using acidic methanol and can be carried out using either conventional or microwave heating. The experiment helps demonstrate acyl…

The aim of this study was to evaluate the effects of living animals on pupils' intrinsic motivation and knowledge. Various studies from the late 1970s and 1980s stress the high effectiveness of authentic learning experiences in pupils' knowledge acquisition. However, there are only few current empirical studies on this topic. The research question…

Proven through more than a decade of rigorous research to be effective with both teachers and students, "Making Sense of SCIENCE" helps teachers gain a deep and enduring understanding of tricky science topics, think and reason scientifically, and support content literacy in science, thereby increasing student achievement. The materials…