The use of systems in many introductory courses is limited and often implicit. Modeling two or more objects as a system and tracking the center of mass of that system is usually not included. Thinking in terms of the center of mass facilitates problem solving while exposing the importance of using conservation laws. We present below three…

Problems on the dynamics of changing mass systems often call for the more general form of Newton's second law Fnet = dp/dt. These problems usually involve situations where the mass of the system decreases, such as in rocket propulsion. In contrast, this experiment examines a system where the mass "increases" at a constant rate and the net force…

Discusses a high school laboratory in which the students take an active role in designing, implementing, and performing experiments concerning basic concepts in physics. (MLH)

The use of computer spreadsheet programs in the physics laboratory is discussed. An example of this application with a conservation of energy laboratory is presented including the cases of a rolling sphere and a sliding sphere. (CW)

Describes an exercise designed for an introductory level calculus-based physics class. Presents a problem on why a rod dipped in water is stable when it is oriented at an angle with the vertical. Discusses qualitative understanding, mechanical understanding using equations, and experimental verification of the problem. (YP)

Described are four musical instruments constructed from polyvinyl chloride (PVC) pipe. The use of computerized synthesizers to play scales and chords is discussed. Suggestions for other illustrations of acoustics are included. (CW)

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)

Demonstrates a laboratory to teach the concept of moment of inertia in which students are asked to identify four objects of equal mass sealed in unopenable containers by identifying the mass distribution of each object. Gives instructions to build an instrument to determine relative distribution of mass. (MDH)