The speed of sound is a physical property that can be measured easily in the lab. However, finding an inexpensive and intuitive way for students to determine this speed has been more involved. The introduction of affordable consumer-grade high-speed cameras (such as the Exilim EX-FC100) makes conceptually simple experiments feasible. Since the…

Describes an experiment demonstrating Lenz's law by measuring a magnet falling through a copper tube compared to a nonmagnet falling. Presents diagrams and pictures showing the apparatus. (YP)

Describes the mechanism of bicycle computers functioning as speedometers and timers. Discusses why the computers do not display the continuously changing readings and show the correct values at higher speeds. (YP)

Described is a mechanically driven device for generating three-dimensional harmonic space figures with different frequencies and phase angles on the X, Y, and Z axes. Discussed are apparatus, viewing stereo pairs, equations of motion, and using space figures in classroom. (YP)

Discusses a group project for a physics laboratory using various pendulums. Presents diagrams of pendulums, describes how to make a pendulum, and provides suggestions for guiding students in the laboratory. (YP)

Describes three experiments with an air table to produce a centripetal force. Provides some diagrams and pictures of the apparatus. (YP)

Described is a physical pendulum experiment with variable pivot as an example of maximizing computer benefits in laboratory interfacing. The laboratory procedures using spreadsheet graphics package are discussed. A diagram of the pendulum, basic formulas, and theoretical curve is provided. (YP)

Investigates the paths of three different points in the rigid body after receiving a sudden blow by a horizontal force. Describes the setup, laboratory procedures, and results with mathematical expressions and ink tracings of the paths. (YP)

Reviews three videotapes for physics teachers: (1) "Determination of the Newtonian Constant of Gravitation" showing the Cavendish experiment; (2) "Preview Film for RAM-Tutor Media" introducing a series of seven videocassettes covering physics; and (3) "Determination of the Velocity of Light" using a rotating mirror. (YP)

Describes a straightforward vertical fall experiment using a badminton shuttlecock, a tape measure, and a millisecond timer. The effects of air resistance are important and directly measurable. The experimental data best fit a predictive model which assumes a resistive force quadratic in the instantaneous speed of the falling object. (GS)

Discusses the equipment and techniques for taking photographs using a sound-actuated trigger. Describes a method using two flash units, two sound triggers, and a high-frequency clock to measure speeds. Provides several high-speed photographs. Lists 11 references. (YP)

Describes three demonstrations showing chaotic motion, which makes long-term prediction impossible. Discusses the apparatus for the demonstrations and procedures for illustrating chaotic motion of pendulum, balls rolling in a double potential well, and a ball rolling on a balanced beam. (YP)

Presents an experiment to show the energy conservation principle using a bow. Describes how to measure the force and work of the bow and the initial velocity of an arrow. (YP)

Defines and discusses jerk, the time rate of change of the acceleration. Presents some cases of jerk with mathematical expressions. Provides questions and problems for classroom use. Lists seven references. (YP)