In early January 2018, after days of subfreezing temperatures, a 20 m waterfall became mostly frozen with supercooled water pouring over the top of the frozen parts of the fall. A video was taken of the waterfalls and supercooled turbulent water flowing on the frozen surface as it turned into frazil ice right before our eyes. Frazil ice consists…

A spreadsheet plotting assignment of real-life data from a racecar is employed to help students master the relationships among speed, acceleration, and distance. The racecar application will capture the imagination and interest of the student. The data is obtained by reading speedometer values from a YouTube video for 40 s as a racecar accelerates…

Pinhole camera photography is explored using a set of entomology pins due to their known pin diameters and availability in a variety of sizes. A procedure to prepare removable-lens digital cameras for pinhole photography is described. A video is included showing a set of ten insect pins and how to fit the camera with pinhole apertures. Formulas…

Care must be taken representing waves traveling in opposite directions. Erroneous results can occur when combining waves with the popular convention where a wave traveling to the right is [psi][subscript R] (x,t) = A sin (kx-[omega]t) and a left-traveling wave is [psi] (x,t) = A sin (kx + [omega]t). An easily overlooked pitfall is pointed out and…

A vacuum cleaner is used to isolate over twelve harmonics in a corrugated toy whistling tube. The toy tube is first taped along a horizontal surface. Then a vacuum cleaner with a hose diameter approximately the same as that for the toy tube is turned on. As the vacuum cleaner hose approaches one end of the corrugated tube, individual higher…

This paper describes a fascinating connection between the physics of music and the famous chord in the dissonant rhythmic section of Stravinsky's "The Rite of Spring" (1913). The analysis of Stravinsky's chord will draw from the physics of harmonics, musical intervals, mathematics, and cognitive psychology. This highly interdisciplinary…

An online HTML5 Fourier synthesizer app is provided that allows students to manipulate sixteen harmonics and construct periodic waves. Students can set the amplitudes and phases for each harmonic, seeing the resulting waveforms and hearing the sounds. Five waveform presets are included: sine, triangle, square, ramp (sawtooth), and pulse train. The…

Students are amazed when I show them a zoo photo of an animal behind a fence and then a zoomed-in photo where the fence has disappeared. They ask 'Where did the fence go?' This paper will explore this magical phenomenon which draws from concepts in photography (angle of view, depth of field) and physics (convex lenses, focal length, real images).…

The classic demonstration illustrating Lenz's law by dropping a magnet through a copper pipe is presented using household aluminum foil right out of the box. Then comes the surprise. The teacher presents an aluminum foil cylinder with a missing lengthwise slice (cut before class). Will the demonstration still work? Students are amazed at the…

The private company SpaceX regularly launches satellites into geostationary orbits. SpaceX posts videos of these flights with telemetry data displaying the time from launch, altitude, and rocket speed in real time. In this paper this telemetry information is used to determine the velocity boost of the rocket as it leaves its circular parking orbit…

Harmonics arise naturally from the resonances in strings and pipes. A video demonstration (Ruiz 2016 "YouTube: Tuba Harmonics" (https://youtu.be/souhEzOP9c4)) is provided where a tubist (coauthor Holmes) produces a phenomenal 24 harmonics using a single tuba pipe length by controlling the buzz of his lips. The frequencies of the…

Costume jewelry beads are employed to demonstrate how a beam of beads are able to transform into a simple pendulum (single bead) where the pendulum length remains constant throughout. These beads are common and inexpensive for instructors, as well as attractive and exciting for students. Beads are removed from the top, keeping the same pendulum…

The basic physics of the flute is presented from the perspective of a professional flutist. The flutist can control loudness, pitch and to some extent timbre. Oscilloscope images are provided to compare changes in these three fundamental sound characteristics. Readers can view a video (Ruiz 2017 "Video: The Flute"…

The harmonics for an open cone with slant length "L" are the same as the harmonics for an open pipe with length "L." When the cone is transformed through phases of closed-open conical frusta into a cylinder of length "L" closed at one end, the fundamental halves and only odd harmonics remain. A simple approach using…

The French horn is used to introduce the three basic properties of periodic waves: amplitude, frequency, and waveform. These features relate to the perceptual characteristics of loudness, pitch, and timbre encountered in everyday language. Visualizations are provided in the form of oscilloscope screenshots, spectrograms, and Fourier spectra to…