Discusses how to stop a spinning object (such as rotating fan blades) by humming and the perception of curious blue arcs around a light. Background information, relevant research, and activities related to these two topics are provided. (JN)

Provides an analysis of the forces causing the erratic motion of a knuckleball. Reveals the manner the ball should be thrown to provide maximum deflection. (Author/CP)

The circular motion observed when water drains into a smooth opening is analyzed. This action, as well as cycloidal atmospheric motion, is explained as the result of rotation of the coordinate system. (CP)

Describes experiments involving variations on the electroscope, an electrostatic toy, a stationary wave machine, a spark counter, a carbon microphone, curvilinear expansion, soap films, a barber's pole, and a simple pendulum. (GS)

Presents activities to teach the concept of projectile motion to high school students using a spring-loaded dart gun, carbon paper, meterstick, ruler, white paper, tape, and a student's desk. (JRH)

Perturbation theory is presented as an invaluable tool for solving a majority of physically interesting problems involving both macroscopic and microscopic objects. Its use in Newtonian mechanics is emphasized.. The method is illustrated with three examples. (KR)

Provides directions for a three person rotating reference system. A series of experiments used with the apparatus is also described. (CP)

Describes an apparatus for an experiment on winding motion in three dimensions. Discusses theory and provides a calculation example. (JM)

Describes a stimulating interactive group project on measuring the lengths of solar days that directly supports concepts related to orbits, motion, and time in a physics or astronomy curriculum, and has the flexibility to extend from a few days to several weeks. Provides new measurement experiences for students and teachers and opportunities for…

Describes construction of an exhibit which uses the acceleration of an elevator to distinguish mass and weight. (CP)

This teacher's guide is based on "DragonflyTV" investigations which focus on real kids doing inquiry-based science investigations. Activities include: (1) "Investigation To Explore Skateboards"; (2) "Investigations To Explore Otters"; and (3) "Investigations To Explore Waterslides." (YDS)