Although ripple tanks have been used in the past to perform wave simulations for electromagnetic and acoustic phenomena, especially before the advent of computers, they are still often used to demonstrate wave propagation in high school and college physics classrooms. Usually ripple tanks have a rectangular shape. The wave propagating through the…

One of the memories of my freshman year at Amherst was a lecture in the required physics/calculus course in which Arnold Arons quoted Isaac Newton on standing on the shoulders of giants. Now that I have spent my physics career, I still use the same quote, but now apply it to the eponymous apparatus that has been designed by the giants in our field.

The ground-breaking image of a black hole's event horizon, which captured the public's attention and imagination in April 2019, was captured using the power of interferometry: many separate telescopes working together to observe the cosmos in incredible detail. Many recent astrophysical discoveries that have revolutionized the scientific…

The Ball Bearing High Voltage generator is a fairly simple and transparent apparatus that can serve as a tool to motivate conceptual descriptions and calculations in electrostatics that are normally presented to our students in a rather dry and matter-of-fact fashion. For example, instead of posing a problem in the typical textbook form of…

During the AAPT summer meeting at Creighton University in 2011, Vacek Miglus and I took pictures of early apparatus at the Creighton physics department. The apparatus in the left-hand picture, shown with the spigot closed, appeared to be a liquid-level device: the water level was the same in both the narrow tube and the flaring glass vase.…

College and university general education (GE) classes are designed to broaden the understanding of all college and university students in areas outside their major interest. However, most GE classes are lecture type and do not facilitate hands-on experimental or observational activities related to the specific subject matter. Utilizing astronomy…

A relatively simple opto-electronic setup is described that utilizes a cadmium sulphide (CdS) photoconductive cell to detect resonance of a stretched vibrating string or wire. The display may be either an oscilloscope or a frequency counter. Also describes an inexpensive socket for flanged-base light bulbs. (JN)

Discusses the conditions under which stereoscopic photographs and drawings may be produced and viewed, and which will show the results of some experimental work. (DF)

Describes the design and use of a projectile motion apparatus to illustrate a variety of projective motion results typically discussed in an introductory course. They include independence of horizontal (constant speed) and vertical (constant acceleration) motions, parabolic path shape, and other types of motion. (JN)

Describes and evaluates the Tel-X-Ometer, its performance, and its accessories. The apparatus, with its low intensity x-ray beam, is specifically designed to make x-ray experiments safe, practical, and affordable for the students. (GA)

Describes a method for demonstrating harmonic motion which utilizes a low frequency oscillator and three oscilloscopes. (SL)

This final article in the series on the fine-beam cathode-ray tube presents: (1) additional investigations; (2) an alternative method for the electron e/m and synchrotron radiation; and (3) two challenges to students (in a dialogue format) together with a lengthy discussion on synchrotron radiation sources. (DH)