Describes a demonstration where two 0.5-kg masses and two 1.0-kg masses are hung on springs on a suspended meterstick. The masses can be made to resonate by putting one partner mass in motion. Relates the motion to the history of the telegraph. (MVL)

Discusses observable phenomena related to air pressure. Describes a simple, unobtrusive, semiquantitative device to monitor the changes in air pressure that are associated with altitude, using a soft-drink bottle and a balloon. (JRH)

Looks at one phase of the water cycle; the formation of drops in cooling water vapor. Examines the influence of surface shape on the equilibrium of the liquid and gas phases. Discusses the mathematical formulas that model the phenomenon. (MDH)

Explains that some metal springs have an initial tension that must be overcome before using the F=kx relationship (Hooke's Law) for experimental calculations in the physics laboratory. (WRM)

Presents a collection of free-body exercises and solutions covering rotational equilibrium and rotational nonequilibrium. (WRM)

Explains the physics behind some of the apparently puzzling aspects of the motion of a person riding a snake-board (a skateboard with independently pivoted axles). (Author/WRM)

Calculates the angular velocity of a spinning top without the simplifying assumption found in most textbooks that the total angular momentum is solely along the symmetry axis. (WRM)

Presents activities and investigations that provide a trail of physics-related topics for students to investigate at a bowling alley. (JRH)

Describes a contest in which students attempt to build a device that produces a donut-shaped air pulse that will travel the greatest distance with the most accuracy. (WRM)

Mathematically explains why the range of a projectile is most insensitive to aiming errors when the initial angle is close to 45 degrees, whereas other observables such as maximum height or flight time are most insensitive for near-vertical launching conditions. (WRM)

Presents hands on science activities using toys on the topics of average speed, acceleration, wavelength, and bouncing balls. (YDS)

Technology-Enabled Active Learning (TEAL) is a pedagogical innovation established in a technology-enhanced multimedia studio, emphasizing constructivist-oriented teaching and learning. In Taiwan, an increasing number of schools are adopting the TEAL notion to deliver courses. This study examines the impact of TEAL on both student performance and…

The angular speed of a spinning object is commonly measured using a stroboscope or a mechanically or optically coupled tachometer. We present here an alternate, simple, and instructive method to measure it using a microphone and a computer.

It is often stated that the physical properties of our universe are "fine tuned"--that is, they must be almost exactly as they are to make the development of intelligent life possible. The implications of this statement, called the "anthropic principle," have been widely discussed in a philosophical context, but the scientific basis for the…

Increasingly widespread agreement exists that the nature of science (NOS) must be an integral element of the K-12 science curriculum with emerging consensus on what specific NOS elements should be the focus of such instruction. In this study reported, eight recent trade books written by NOS experts addressing the nature of science for the general…