Magnetic braking is a long-established application of Lenz's law. A rigorous analysis of the laws governing this problem involves solving Maxwell's equations in a time-dependent situation. Approximate models have been developed to describe different experimental results related to this phenomenon. In this paper we present a new method for the…

We present an experiment, well adapted for students of introductory optics courses, for the visualization of the impact of spherical aberration in the point spread function of imaging systems. The demonstrations are based on the analogy between the point-spread function of spherically aberrated systems, and the defocused patterns of 1D slit-like…

This paper revisits the demonstration of Lenz by dropping magnets down a non-magnetic tube. Recent publications are reviewed and ideas for undergraduate laboratory investigations are suggested. Finally, an example of matching theory to observation is presented. (Contains 4 tables, 5 figures and 3 footnotes.)

The synthesis of "N"-benzyl-2-azanorbornene via aqueous hetero Diels-Alder reaction of cyclopentadiene and benzyliminium chloride formed in situ from benzylamine hydrochloride and formaldehyde is described. Characterization of the product was achieved by IR and NMR spectroscopies. The spectral data acquired are thoroughly discussed. Numerous…

Normal mode solutions for the perfectly flexible hanging cord problem have been known for over 200 years. More recently, theoretical results for a hanging cord with a point mass attached were presented. Here the theoretical results are tested experimentally using high-precision techniques which are accessible for use in an introductory laboratory.…

State and district science standards typically call for students to take part in hands-on labs and experiments in the elementary grades. The 1996 National Science Education Standards, which were written by the National Research Council and serve as a reference for many states, emphasize similar activities. Yet the use of even simple labs and…

There has been a recent call for the use of more systematic thought experiments when investigating learning. This paper presents a storyboarding method for capturing and sharing initial ideas and their evolution in the design of a mathematics learning task. The storyboards produced can be considered as "virtual data" created by thought experiments…

Alaryngeal speakers (speakers in whom the larynx has been removed) have inconsistent control over acoustic parameters such as F[subscript 0] and duration. This study investigated whether proficient tracheoesophageal and oesophageal speakers consistently convey phrase boundaries. It was further investigated if these alaryngeal speakers used the…

Inquiry is a goal of science education reform. Middle school science teachers and their students can develop understanding of inquiry by using an experimental design format. Facilitating this format with the four-question strategy helps students to design their investigations. An example of varying concentrations of vinegar and water illustrates…

A variety of experimental evidence indicates that the memory representation for multiplication facts (e.g., 6 [times] 9 = 54) incorporates bidirectional links with a forward association from factors to product and a reverse association from product to factors. Surprisingly, the authors did not find evidence in Experiment 1 of facilitative…

According to Crain and Nakayama (1987), when forming complex yes/no questions, children do not make errors such as "Is the boy who smoking is crazy?" because they have innate knowledge of "structure dependence" and so will not move the auxiliary from the relative clause. However, simple recurrent networks are also able to avoid…

It is challenging for biomedical engineering programs to incorporate an indepth study of the systemic interdependence of cells, tissues, and organs into the rigorous mathematical curriculum that is the cornerstone of engineering education. To be sure, many biomedical engineering programs require their students to enroll in anatomy and physiology…

Describes an experiment that provides a study of the different colors and shapes of crystals of transition metal dimethylglyoxime complexes with the use of a low power microscope. Discusses the preparation and examination of the crystals. (CW)

Throughout history human subject research has been plagued by researchers whose studies were riddled with danger and/or risk to their subjects. Indeed, one may cite numerous situations where human subjects were injured and/or killed in experiments that were designed with no thought or anticipation of risk to the subjects. As a result, the federal…

Purpose: The purpose of this paper is to propose an indexing and teaching focus mining system for lecture videos recorded in an unconstrained environment. Design/methodology/approach: By applying the proposed algorithms in this paper, the slide structure can be reconstructed by extracting slide images from the video. Instead of applying…