This is the fourth paper in our Light-Emitting Diodes series. The series aims to create a systematic library of LED-based materials and to provide readers with the description of experiments and the pedagogical treatment that would help their students construct, test, and apply physics concepts and mathematical relations. The first paper provided…

I am a volunteer reader at the Princeton unit of "Learning Ally" (formerly "Recording for the Blind & Dyslexic") and I recently discovered that high school students are introduced to the concept of quantization well before they take chemistry and physics. For the past few months I have been reading onto computer files a…

Argues that high school teachers have given up on trying to teach equations and mathematics to poorly prepared, inner-city, or very average students. Describes a mathematical problem-solving physics course for all types of students from average to honors. (CCM)

Provides six short story problems that are solved using common physics concepts. Includes solutions. (MVL)

Presents part seven of a continuing presentation of exponential functions. Provided is an extension of the part six discussion, exponential population growth, to world population growth. (SL)

Discusses laboratory investigations designed to allow students to solve problems without using predetermined mathematical formulas. As a result, laboratory problems force students to think. In addition, some students formulate their own mathematical relationships and enhance their understanding of the connection between mathematics and…

Presented are problems that teachers can use to stimulate students' thinking about the subject of mathematical scaling. Food and eating examples are used to illustrate this concept. (CW)

Uses projectile motion to explain the two roots found when using the quadratic formula. An example is provided for finding the time of flight for a projectile which has a negative root implying a negative time of flight. This negative time of flight also has a useful physical meaning. (MVL)

Solutions for a problem in which the time necessary for an object to fall into the sun from the average distance from the earth to the sun are presented. Both calculus- and noncalculus-based solutions are presented. A sample computer solution is included. (CW)

Uses the problem of determining when a car and truck traveling at the same speed will collide after the truck has applied its brakes to illustrate the need to consider boundary conditions when solving problems in elementary mechanics. (MDH)

Presents a motion problem that students in a college physics class are asked to solve and later asked to continue to analyze until they have stopped learning from the problem or the problem itself is finished. (MDH)

Develops the idea of fractals through a laboratory activity that calculates the fractal dimension of ordinary white bread. Extends use of the fractal dimension to compare other complex structures as other breads and sponges. (MDH)