In this paper, an educational tool is proposed to show the internal photoelectric effect in a simple and clear way for Undergraduate Physics courses or High Schools. Experimental evidence of the photoelectric effect is particularly important in the didactic experience. This effect is fundamental to introduce students to the world of quantum…

Time-resolved luminescence lifetime measurements are an important photophysical technique. However, access to this technique at the undergraduate level is limited by the expense of the instrumentation needed to create the well-defined light pulses required to measure the luminescence decay of an excited state molecule. We present here an…

LED (light-emitting diode) technology is moving fast, and with justification, some facility managers have viewed it with a wary eye. Some LEDs on the market do not perform as promised, and the technology is changing rapidly. But new developments from the U.S. Department of Energy (DOE) now make it easier for facility managers to find LEDs that…

Oregon Mathematics, Engineering, Science Achievement (MESA) focuses its afterschool programs with middle and high school students on inventions that address key problems in developing countries, such as sustainable lighting, water transportation, water filtration, and prosthetics. With the support of a grant from the Oregon Community Foundation,…

A bridge rectifier is a diamond-shaped configuration of diodes that serves to convert alternating current(AC) into direct current (DC). In our world of AC outlets and DC electronics, they are ubiquitous. Of course, most bridge rectifiers are built with regular diodes, not the light-emitting variety, because LEDs have a number of disadvantages. For…

After watching a shirt being wafted into the air as it dries over a hearth, the tinkerer Joseph Montgolfier decides to try lighting a fire under a balloon--and creates the first flying machine. After observing an art object swinging from a cathedral's ceiling, Galileo mulls over the mechanisms of a pendulum-driven clock--and produces one 50…

Far from the limelight of LEED, Energy Star or Green Globes certifications are the energy codes developed and updated by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) and the International Code Council (ICC) through the support of the Department of Energy (DOE) as minimum guidelines for building envelope,…

A new device for teaching the physics of sound, specifically demonstrating the wavelengths of standing sound waves, is here described. I define a "Lincoln's Tube" as any hollow tube that uses lights (LEDs typically) to demonstrate the presence of sound standing waves. The name is chosen intentionally to recall a Ruben's Tube or a Kundt's…

Going "green" is a slogan that is very contemporary, both with industry and in the political arena. Choosing more energy-efficient devices is one way homeowners can "go green." A simple method is to change home lighting from hot incandescent bulbs to compact fluorescent lights (CFLs). But do they really save energy? How do their illuminations…

We safely remove the outer glass bulb from an incandescent lamp and burn up the tungsten filament after the glass is removed. This demonstration dramatically illustrates the necessity of a vacuum or inert gas for the environment surrounding the tungsten filament inside the bulb. Our approach has added historical importance since the incandescent…

Focusing on the 5-year period from 1987 through 1991, this report provides data on Pasadena City College (PCC) in California, reviewing efforts and achievements in improving institutional productivity. Following a brief opening section discussing productivity trends and issues in the American workforce and in higher education, discussions are…

This article describes the Systems and Global Engineering (SAGE) Project in which students collaborate with others from around the world to model solutions to some of today's most significant global problems. Stevens Institute of Technology and the New Jersey Technology Education Association (NJTEA) have teamed up to develop innovative…

The College of Lake County Regional Photonics Initiative project was motivated in part by the hiring of out-of-state technicians for local Photonics industry positions. Fifteen high paying employment opportunities during the recent recession could not be filled from the locally available workforce. Research on the current demand and future growth…

While "Dancing With the Stars" often shares the background of the dancers and shows some of the preparation that goes into the dances, it does not always give viewers the background of the dances being danced. Many people are never knowledgeable about where dances came from or how they began. In this article, the author provides some…

Started in late 1972, "Operation Conserve" has led to a central control system and reduced lighting methods that have cut the University of Western Ontario's energy use by 15 percent. (Author)