Historically, classical thermodynamics was developed during attempts to improve the efficiency of steam engines. Those investigations led to the well-known zeroth, first, and second laws of thermodynamics. Although these laws are presented independently, linkages between the zeroth and second laws have been pointed out in the physics teaching…

During the early decades of the 18th century, Newtonian physics was still new. Much effort was expended in testing its validity. One arena in which evidence could be found was the shape of Earth. Was it perfectly spherical? On the observational side there were two hints. In 1671 Jean Richer had measured the rate of ticking of a pendulum clock near…

In high school, and also in introductory physics courses in higher levels of schooling, the law of universal gravitation of planets is introduced by postulating Johannes Kepler's three laws, and later Isaac Newton's law of the inverse of the square of the distance to the Sun. The justification of the laws is only achieved in advanced courses in…

Archimedes' principle has been and still is a complicated concept to understand by introductory students, especially as typically stated in physics textbooks. Take for example its statement by Bierman: "When a body is fully or partially submerged in a fluid, a buoyant force from the surrounding fluid acts on the body. The force is directed…

Newton's laws are essential for understanding causes and description of mechanical motion. Great attention is paid to them during physics education. Unfortunately, many students, not only in high school, but also undergraduates, can recite them but do not understand their essence. Therefore, it is useful to demonstrate different experiments in the…

A classic, life science-themed fluid dynamics scenario is blood flow through a constriction. Physics teachers traditionally ask students if the pressure experienced by the blood in the constriction is greater, lesser, or the same as before the constriction. The conventional approach to resolving this question calls upon the equation of continuity,…

Many of the old demonstrations in electricity and magnetism can be performed more effectively and with greater visual appeal by using newly available neodymium magnets and color LEDs. For this reason several demonstrations, commonly used for teaching electromagnetic induction and Lenz's law, have received renewed attention in recent years. In…

The stereotypical situation of a snowball picking up both mass and speed as it rolls without slipping down a hill provides an opportunity to explore the general form of both translational and rotational versions of Newton's second law through multivariable differential equations. With a few reasonable assumptions, it can be shown that the snowball…

Although nearly everyone is familiar with colors from an early age and the fundamentals of color mixing are taught at various abstraction levels throughout kindergarten to high school, we repeatedly observe that our student teachers in physics have problems in explaining the subject. Therefore, we propose an experimental setup that focuses on the…

Over the past several years, we have contributed articles to "TPT" that focus on a forensics-style reexamination of significant historical events. The purpose of these articles is to afford students the opportunity to apply basic principles of physics to unsolved mysteries and potentially settle the historical debate. We assembled the…

Most springs do not simply obey Hooke's law because they are constructed to have an initial tension, which must be overcome before normal elongation occurs. This property, well known to engineers, is universally neglected in elementary physics courses. In particular, the standard simple harmonic motion experiment omits any discussion of this…

Measuring magnetic induction is occasionally performed by our students during their academic training in physics. Among the various methods used to measure it, the Hall effect is the most common and widespread. Another way consists of employing an electronic flux-meter. It is constituted by a small flat coil (SFC) connected to the input of an…

An important step in learning to use math in science is learning to see symbolic equations not just as calculational tools, but as ways of expressing fundamental relationships among physical quantities, of coding conceptual information, and of organizing physics knowledge structures. In this paper, I propose "anchor equations" as a…

The role of work and mechanical energy in classical relativity has been a subject of renewed interest in this publication. Here we present a problem that illustrates the relationship between impulse and kinetic energy for a rocket-powered object that can also change its gravitational potential energy. The same introductory physics principles lead…

Students should have a strong conceptual understanding of the connection between force and acceleration before they start working with applications and problem solving. This has been discussed in the literature. During these days of flipped classroom instruction, an at-home activity could be especially valuable. I will describe an experiment with…