In this article, the authors discuss a unique and challenging laboratory exercise called, the paint-stir-stick submarine, that keeps the students enthralled. The paint-stir-stick submarine fits beautifully with the National Science Education Standards Physical Science Content Standard B, and with the California state science standards for physical…

An experiment is suitable for fourth-year undergraduate and graduate students in which the nature of the semiconductor materials through determination of flat-band potential using the Mott-Schottky equation is explored. The experiment confirms the soundness of the technique.

A simple and cost-effective experiment for the development and characterization of semiconductors using Uv-vis spectroscopy is described. The study shows that the optical properties of ZnO films can be easily modified by forming Zn[subscript 1-x] Co[subscript x]O solid solutions via spray pyrolysis.

Students developing their labs lead them to enhance the laboratory experience. This benefits the students as they learn more about the experiments and they get benefit by peers led labs through a more fluid discussion.

Students should understand both the science and the engineering models of experimentation. Since students are often predisposed to using the engineering model, teachers must intentionally design activities that better reflect the nature of scientific experimentation. In this article, the authors recommend some guidelines that can be used when…

We consider a simple oscillator that exhibits harmonic and anharmonic regimes and analyse its behaviour over the complete range of possible amplitudes. The oscillator consists of a mass "m" fixed at the midpoint of a horizontal rope. For zero initial rope tension and small amplitude the period of oscillation, tau, varies as tau is approximately…

A computational experiment aimed to create and systematically analyze models of simple cation hydrates is presented. The changes in the structure (bond distances and angles) and the electronic density distribution of the solvent and the thermodynamic parameters of the hydration process are calculated and compared with the experimental data. The…

When most materials are heated they expand. This concept is usually demonstrated using some type of mechanical measurement of the linear expansion of a metal rod. We have developed an alternative laboratory method for measuring thermal expansion by using a Michelson interferometer. Using the method presented, interference, interferometry, and the…

Teaching "scientific method" has long been a regular part of science education, and many curriculum standards call for it. But it has run into a variety of criticisms, which add up to the charge that it conveys an unrealistic and unappealing view of science. In this article, the authors discuss how science really works and provide different ways…

In this paper we analyse the behaviour of a small-scale model of a magnetic levitation system based on the Inductrack concept. Drag and lift forces acting on our prototype, moving above a continuous copper track, are studied analytically following a simple low-speed approach. The experimental results are in good agreement with the theoretical…

We apply several physical ideas to determine the steady temperature distribution in a medium moving with uniform velocity between two infinite parallel plates. We compute it in the coordinate frame moving with the medium by integration over the "past" to account for the influence of an infinite set of instantaneous point sources of heat in past…

We study the turning point problem of a spherical pendulum. The special cases of the simple pendulum and the conical pendulum are noted. For simple initial conditions the solution to this problem involves the golden ratio, also called the golden section, or the golden number. This number often appears in mathematics where you least expect it. To…

Efficient glow-in-the-dark materials are usually difficult to synthesize and need complex experiments with long reaction times that are not appropriate for conventional lab teaching. Therefore, we describe a new experimental procedure that allows the production of one of the most efficient "glow-in-the-dark" materials (SrAl[subscript 2]O[subscript…

Mr. Smith and Ms. D'Amico are two veteran science teachers in a well-performing school district. Both teachers use weekly lab exercises and experiments as formative assessments. In their middle school classrooms, children are engaged and eager to learn. As students walk into Mr. Smith's classroom, a prescribed, step-by-step procedure of the day's…

The European Association for Astronomy Education (EAAE), in collaboration with the Bibliotheca Alexandrina of Egypt and the participation of schools from all around the world, performed the Eratosthenes experiment on 21 June 2010. This activity has been selected as one of the finalists in the 11th international prize organized by Ciencia en…