Presents the theory behind the mechanics demonstration that involves projecting a ball vertically upward from a ballistic cart moving along an inclined plane. The measured overshoot is believed to be due, in part, to the presence of rolling friction and the inertial properties of the cart wheels. (JRH)

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)

Describes differences between engineers' and physicists' views of free-body diagrams (FBD). (PR)

Describes how a real life experience was used to illustrate linear and rotational equilibrium (ZWH)

Uses the top three inches of a bucket with a vertical notch about three inches wide removed to demonstrate centripetal force and the minimum size of opening needed for a ball rolling inside to leave. Provides a mathematical explanation. (MVL)

Provides a period-long activity using battery powered cars rolling in a circular motion on a tile floor. Students measure the time and distance as the car moves to derive the equation for centripetal acceleration. (MVL)

A study of time in Newtonian physics is presented. Newton's laws of motion, falsifiability and physical theories, laws of motion and law of gravitation, and Laplace's demon are discussed. Short bibliographic sketches of Laplace and Karl Popper are included. (KR)

This activity makes a barometer out of 50 feet of clear vinyl tubing and a gallon of tea. The barometer is used in a building stairwell where students have easy access to the tube. Discusses possible pitfalls, vapor pressure, elevation, and weather influences. (MVL)

Presents instructions for putting a hard-boiled egg inside a bottle whose opening is slightly smaller than the egg's circumference, and for getting the egg out of the bottle. Also describes variations of the demonstration such as cooling the flask or using a banana. Cites incorrect and correct explanations of the demonstrated phenomenon. Contains…

Presents Newton's main ideas for the formulation of classical mechanics as given in the Principia. Discusses Ernst Mach's criticisms of Newtonian mechanics as contained in his book, "The Science of Mechanics". Analyzes the influence of Mach's ideas in the teaching of classical mechanics by considering five textbooks. Concludes that…

Reports the results of various concepts held by children of different ages dealing with weight, heaviness, gravity, and force. (PR)

Describes an activity to give students experience with the variables and forces impacting a moving body on an inclined plane by observing a ball as it rolls down an inclined PVC pipe of fixed length. Includes a student worksheet. (MKR)

Presents an approach that provides a simple and adequate procedure for introducing the concept of rolling friction. Discusses some aspects related to rolling motion that are the source of students' misconceptions. Presents several didactic suggestions. (JRH)

Describes systems used to introduce students to the concept of torque and discusses the effects that puzzle the beginner in the introductory lab. (JRH)

Presents the results of a discussion among high school students about what holds up the moon. The question and ensuing discussion enabled students to question their existing ideas, but caused them to be anxious. (DDR)