Students in environmental sciences, ecology, or wildlife management are often reluctant to acquire training in basic laboratory techniques. To advocate the importance of this training, we reviewed literature in the fields of biological and environmental science for one frequently used technique--centrifugation--and evaluated whether centrifugation…

We consider a volume of air trapped over a glycerol column in a eudiometer. We demonstrate that there is an approximately linear relationship between the volume of trapped air and the height of the glycerol column. Simply by moving the eudiometer up and down, we cause the glycerol-column height and trapped-air volume to vary. The plot of volume…

The speed of sound is a physical property that can be measured easily in the lab. However, finding an inexpensive and intuitive way for students to determine this speed has been more involved. The introduction of affordable consumer-grade high-speed cameras (such as the Exilim EX-FC100) makes conceptually simple experiments feasible. Since the…

The inherent spatial complexity of the human cerebral ventricular system, coupled with its deep position within the brain, poses a problem for conceptualizing its anatomy. Cadaveric dissection, while considered the gold standard of anatomical learning, may be inadequate for learning the anatomy of the cerebral ventricular system; even with…

It is important for students to be exposed to the concept of osmotic pressure. Understanding this concept lays the foundation for deeper discussions that lead to more theoretical aspects of water movement associated with the concepts of free energy, water potential, osmotic potential, pressure potential, and osmotic adjustment. The concept of…

All-pass filter systems can be used in laboratory experiments in the physics and psychophysics of sound and music. Particular applications, such as lateralization of sounds in headphone listening, are presented. (BB)

Describes simple speckle photography experiments which are easy to set up and require only low cost standard laboratory equipment. Included are procedures for taking single, double, and multiple exposures. (JN)

Presents an alternative method for measuring the electronic charge using data from the electrolysis of acidified distilled water. The process (carried out in a commercially available electrolytic cell) has the advantage of short completion time so that students can determine electron charge and mass in one laboratory period. (DH)

A low-cost procedure for metallizing a silicon p-n junction diode by electroless nickel plating is reported. The procedure demonstrates that expensive salts can be excluded without affecting the results. The experimental procedure, measurement, results, and discussion are included. (Author/KR)

Describes the use of 35 mm slides consisting of a diagram of photograph and 15 to 60 words of text to augment laboratory instruction. (GS)

Deals with the subject of laser hazards, laser hazards control, and laser safety practices in the laboratory. Describes four categories of hazards: radiative, electrical, explosive, and toxic, and explains the status of federal regulations that seek to define lazer hazards and control safety standards. (Author/GS)

Background information and procedures are provided for an optics experiment related to diffraction order asymmetry. (JN)

Suggests experiments to help develop understanding of photoconductivity, photometry, and the inverse square law in optics. The design of a simple absorption colorimeter is also described. (DH)

Presents background information, materials, calculations, and laboratory procedures for a physical chemistry experiment focused on the thermodynamics of a galvanic cell. (JN)