A container was placed on top of a piece of white paper, and a pin positioned so that it vertically touched an outside wall of the container. Students were asked to predict the image of the pin when it was observed from the top of the container. Two scenarios of either an empty container or a container completely filled with water were considered…

Experiments are described on collisions between two billiard balls and between a bat and a ball. The experiments are designed to extend a student's understanding of collision events and could be used either as a classroom demonstration or for a student project.

A "one-pot" method for acquiring kinetic data for the reactions of a series of substituted aromatic esters with potassium hydroxide using [supserscript 13]C NMR spectroscopy is described, which provides an efficient way to obtain sufficient data to demonstrate the Hammett equation in undergraduate laboratories. The method is…

We present a hands-on, inquiry-based activity exploring how CO[subscript 2] input to seawater affects the skeletons of several species of reef-building corals and other marine organisms by testing for changes in pH and calcium ion concentrations. Originally developed to inspire and recruit high school students in the state of Hawai'i into the…

Each May a Slovenian science extravaganza called Znanstival (Sciencetival, www.sciencetival.si) fills the streets and other public venues with the excitement of science. Organized by the staff of Hisa eksperimentov (House of Experiments or simply HE, www.he.si), a jewel of a science museum located in the Slovenian capital of Ljubljana, the annual…

In 2010, the Wiimote was upgraded with three-axis gyroscopes that can measure rotational velocities up to 2000 deg/s. The improved remote is referred to as the Wii MotionPlus. We present experiments that use the gyroscope's capabilities and compare data acquired in lab settings with those obtained in playground environments. Van Hook et al.…

The inverse-square law for the intensity of light received at a distance from a light source has been verified using various experimental techniques. Typical measurements involve a manual variation of the distance between a light source and a light sensor, usually by sliding the sensor or source along a bench, measuring the source-sensor distance…

In a recent issue of "TPT," Gordon Gore made interesting observations about the red or yellow fluorescence when laser beams are passed through olive oil. With the excellent visuals contained in that article, we present a pictorial explanation of the questions that were raised in Ref 1 ("Fun with Fluorescence in Olive Oil,"…

Typical commercial solar panels consist of approximately 60 individual photovoltaic cells connected in series. Since the usual Kirchhoff rules apply, the current is uniform throughout the circuit, while the electric potential of the individual devices is cumulative. Hence, a solar panel is a good analog of a simple resistive series circuit, except…

In our teaching practice, we find that a large number of first-year university physics and chemistry students exhibit some difficulties with applying Newton's third law to fluids because they think fluids do not react to forces. (Contains 1 table and 3 figures.)

We present a number of simple demonstration experiments recorded with high-speed cameras in the fields of gas dynamics and thermal physics. The experiments feature relatively slow combustion processes of pure hydrogen as well as fast reactions involving oxy-hydrogen in a stoichiometric mixture. (Contains 4 figures.)

Creativity has become a hot topic in education. From President Barack Obama to Amazon's Jeff Bezos to "Newsweek" magazine, business leaders, major media outlets, government officials, and education policy makers are increasingly advocating including student creativity in the curriculum. But without a clear understanding of the nature of creativity…

After a brief history of the Levitron, the first horizontal axis Levitron is reported. Because it is easy to operate, it lends itself to educational physics experiments and analogies. Precession and nutation are visualized by reflecting the beam from a laser pointer off the "spignet". Precession is fundamental to nuclear magnetic…

This experiment and analysis offer an effective experience in greenhouse gas reduction. Ammoniated water is flowed counter-current to a simulated flue gas of air and CO2 in a packed column. The gaseous CO2 concentrations are measured with an on-line, non- dispersive, infrared analyzer. Column operating parameters include total gas flux, dissolved…

Proper hand hygiene accompanied with environmental surface disinfection provides a comprehensive approach to control and prevent respiratory and gastrointestinal illness in schools, hospitals, work environments, and the home. The persistent non-pathogenic Nora virus common in "Drosophila melanogaster" provides a horizontally transmitted…