The Wilson cloud chamber is an apparatus used for detecting and observing the trails of alpha/beta rays or even cosmic rays in saturated gas conditions. The principle of this device is based upon the powerful ionization of the aforementioned rays within the medium. This article will provide instruction for creating a classic version of the cloud…

There are hundreds of satellites in orbit around Earth. Readily available data about them can be a treasure trove for investigations by students at all levels. Orbital parameters and energy changes can be explored. Many of these satellites transmit signals that can be detected by an inexpensive radio receiver--a scanner--designed to receive FM…

Space telescopes are some of the most precise and complicated machines ever built. Not only must they survive the harshness of space travel, but they also need to be incredibly accurate: misalignments by fractions of a millimetre can have huge effects on the quality of the images they capture. In 1990, the Hubble Space Telescope became the first…

An NMR tube cleaner that is quickly and easily constructed from everyday laboratory equipment is described. This cost-effective option removes the need to purchase a fragile, more expensive model. The small footprint of the device lends itself to being given a permanent place in the laboratory, but it is also simple enough to disassemble and…

In an earlier article I argued that much of what used to be called "modern physics" stems from the intersection of two earlier technologies: high vacuum and high voltage. In this article I will discuss the induction coil, invented in the 1830s, reinvented in the second half of the 19th century, and still used today to produce the high…

A Finderscope is a low-power telescope with a relatively large field of view. It has the same line of sight as the main telescope, helping the main telescope easily find the target. One of the differences between a telescope and a finder is that the finder has crosshairs to aid in accurately pointing at a target. You can see the crosshairs and the…

In this article, we present an intriguing experimental exercise that does not fall foul of improper use of instrumentation. The activity is designed as an electronics exercise where the role of the instruments in the measurement of the RC time constant is considered. Essentially, we study the accuracy and precision of a measurement of the RC time…

Chemical safety is a discipline that cuts across all other chemical disciplines and also impacts other laboratory sciences. It is an essential part of chemistry and continues to evolve with the science it supports. This paper provides a short background about ACS's growing involvement with chemical safety education that stems from support from ACS…

This work describes the design and testing of a low-cost light-emitting diode (LED)-based nephelometer for turbidity analysis. It also describes the use of this nephelometer for context-based learning (CBL) experiments designed for teaching laboratories. The LED nephelometer is simple, low-cost, and robust, providing similar results as a…

Drop Tower Physics (DTP) is composed of a set of experiments using standard physics lecture demonstration equipment, such as a pendulum, mass spring oscillator, and so forth, while videotaping them as they fall freely in the Dryden Drop Tower in Portland, OR. An article published in "The Physics Teacher" illustrated the behavior of a…

Prompt determination of the positive or negative signs of charged objects promotes students' understanding of electrostatics and motivates them to learn more about this field of physics. We developed a low-cost (about US$5) and easy-to-use device for checking the signs of the static charges in objects. It consists of two easy-to-build circuits,…

We report the design of a low-cost electrochemical workstation and open-source graphical user interface capable of performing a variety of electrochemical methods in an undergraduate teaching laboratory. The instrument--based on the popular Arduino microcontroller board--can be constructed from common components for $40 USD. The modular design of…

The article presents simple outdoor experiments for measuring illuminance on inclined surfaces with a luxmeter. A hill model is used to investigate the difference in illuminance between a sunny side and a shady side of a hill, with up to a fivefold difference found between the two sides on a sunny day. The illuminance of the sunny side of the hill…

Photogates play an important part of many of today's physics laboratory experiments. They signal when an infrared (IR) beam is interrupted, thus supplying the experimenter with important timing information. Currently photogates use an infrared photodiode (IR transmitter) and a phototransistor (IR receiver). User-built photogates have a weakness…

Although it originates from the ancient Greeks, optics still arouses a lot of scientific interest, mainly due to the technological innovation associated with it. One of its most interesting applications is related to optical metrology and the characterization of materials through optical techniques. While some of these processes can be explained…