The early 20th century marked a number of transformational experimental and theoretical discoveries in physics. Among them is one that is often neglected in the introductory physics curriculum, which revolutionized our understanding of the molecular world. Evidence for the thermal motions of atoms was first observed by Perrin in 1909, which had…

The use of toys as teaching aids in physics classrooms has a rich history, and the role of play in science education is a well-established line of research. Much of what has been written on the topic has included discussions of specific toys and the implications of using those toys to teach physics. One of the toys from my childhood that seems to…

The dynamics of yo-yo motion are considered in this article. Many textbooks have examined the "rolling" motion of a yo-yo as it moves vertically up or down. However, in the vicinity of the lowest point, a jerk in the string occurs as the center of mass transitions from a linear motion to a pure rotational motion (with respect to the end…

There are many examples of using smartphones in physics experiments. Students and teachers can easily perform many physics experiments with the help of smartphone sensors, even experiments for which high-cost materials are needed. There are different types of such experiments in which various kinds of sensors are used. Many physical quantities can…

The PhiTOP® (or FTOP®) is a physics toy designed not only to act as a spinning top but also to appeal to the eye and to the scientifically curious mind.1 It is currently made in two versions, one from solid aluminum and the other solid brass. Each top is highly polished, and is elliptical in one cross section and circular in another. Its name…

In this article, the dynamics of a traditional toy, the yo-yo, are investigated theoretically and experimentally using smartphone sensors. In particular, using the gyroscope the angular velocity is measured. The experimental results are complemented thanks to a digital video analysis. The concordance between theoretical and experimental results is…

The Michelson interferometer is one of the key experiments in modern physics when it comes to the topic of interference (Box 1). Experiments using interferometry have a high historic relevance as well as uses in current areas of research (quantum erasers, gravitational wave detection) and are used in higher education. Because of the high cost of…

The ubiquitous bouncy ball, or "superball," is an engaging child's toy that has endured for more than 50 years. But what makes a bouncy ball so uniquely suited to its name? Steel balls, for example, are more highly elastic than are butadiene bouncy balls. Yet it is butadiene balls, and not steel balls, that appear in toy stores and…

Nowadays, in almost any country in the world, it is difficult to find a young person who has never played with, seen, or heard of the most famous toy in 2017: the fidget spinner. According to Wikipedia: "The fidget spinner is a toy that consists of a ball-bearing in the center of a multi-lobed flat structure made from metal or plastic…

Students are well aware of the effect of the deflection of sports balls when they have been given a spin. A volleyball, tennis, or table tennis ball served with topspin results in an additional downward force that makes the ball difficult to catch and return. In soccer, the effect of sidespin causes the ball to curve unexpectedly sideways,…

Toys are known to attract interest in physics and they are therefore often used in physics teaching of various topics. The present paper deals with a simple toy, the so-called "hopper popper," which, similar to superballs, can be used when teaching mechanics. We suggest some experiments and describe the basic physics of this toy, also…

A popular demonstration involves placing a yo-yo on a level table and gently pulling the string horizontally when it is wrapped to come out below the center of the yo-yo's axis. Students are then asked to predict which way the yo-yo will move. A similar demonstration is performed with a tricycle by pulling forward on a pedal with the pedal down in…

Many students have owned or seen fluids toys in which two immiscible fluids within a closed container can be tilted to generate waves. These types of inexpensive and readily available toys are fun to play with, but they are also useful for provoking student learning about fluid properties or complex fluid behavior, including drop formation and…

The drop towers of yesteryear were used to make lead shot for muskets, as described in "The Physics Teacher" in April 2012. However, modern drop towers are essentially elevators designed so that the cable can "break" on demand, creating an environment with microgravity for a short period of time, currently up to nine seconds at…

A $1 plastic helicopter toy (called a Wacky Whirler) can be used to demonstrate lift. Students can make basic measurements of the toy, use reasonable assumptions and, with the lift formula, estimate the lift, and verify that it is sufficient to overcome the toy's weight. (Contains 1 figure.)