It has long been suspected by general relativists that physicists who do not specialize in general relativity (GR) believe that special relativity (SR) is incapable of modeling dynamics within accelerated reference frames. Consequently, many physicists may conclude that certain phenomena, such as time dilation due to acceleration, can only be…

Although diffusion is the subject of beginning chemistry classes, there are a variety of experiments, such as the spread of perfume in the classroom, that are often "incorrectly" explained by diffusion alone. To eliminate this common misconception, a recently published method is modified to determine the diffusion constant of hydrogen…

In traditional introductory physics courses, concepts of distance, displacement, speed, velocity, scalars, and vectors are generally taught near the beginning of the course. However, students often contend with preexisting notions, such as the idea that speed and velocity are synonyms, which present some of the first conceptual hurdles that they…

Student misconceptions of the double-slit experiment (Fig. 1) are abundant. The most common ones that we observe include: (1) belief that constructive interference requires both pathlengths to be integer multiples of the wavelength ("L[subscript 1] = n[subscript 1][lambda]" and "L[subscript 2] = n[subscript 2][lambda]") rather…

The concept of redshift is very often used in teaching physics and astronomy, as well as in science public outreach. Redshift is an interesting topic, used to describe many physical processes such as the Doppler effect or the expansion of the universe. Nevertheless, there are unfortunately also misconceptions about redshift. When facing the…

In order to fix some important concepts of Fundamental Physics, either because they are not usually discussed in depth in theoretical classes and much less at laboratories, or because they are not sufficiently developed in textbooks, it is more effective not to tackle them directly, but to propose a mental or practical experiment to attract the…

Despite being established as genuine physical features of the universe, black holes are not well understood at a non-technical level. Basic features of black holes are outlined, a few of the more popular misconceptions surrounding them are listed and their errors identified.

Electric charges and magnetic poles are often confused in the minds of students. It is convenient to remind them that they only interact when they are in relative motion. The force F on a charged particle q moving with velocity V in a magnetic field B is given by F = qVxB. By Newton's Third Law, the force on magnet producing the field B is equal…

Every so often an article appears in the popular press pointing to the apparent confusion surrounding the topic of aerodynamic lift and alleging that even the "experts" don't fully understand it. This makes attention-grabbing copy, but it overstates the case. Actually, the science of lift is not in dispute. It is well understood in terms…

This chapter illustrates the main warning signals that could help us to detect the flaws of an explanation in physics: internal contradiction (two examples); direct contradiction of a law of physics (one example); indirect contradiction of a law of physics (one example); logical incompleteness of an explanation (three examples); overgeneralization…

Recently, the physics education community has taken a keen interest in modernising physics education. However, while topics in modern physics have great potential to engage students, these topics are abstract and hard-to-visualise. Therefore, many students hold mistaken pictures and misconceptions, which can impede learning. In this article, we…

Before reading this essay, go to your kitchen and find a bottle of Italian salad dressing. Get one that has been sitting still for a while at a fixed temperature--that is, one in thermal equilibrium. You will find an oil-rich layer at the top of the bottle and a vinegar-rich layer at the bottom (see Fig. 1). But think for a moment before spreading…

A popular physics legend holds that scissors can cut paper with a speed faster than light. Here this counter-intuitive myth is investigated theoretically using four simple examples of scissors. For simplicity, all cases will involve a static lower scissors blade that remains horizontal just under the paper. In the first case, the upper blade will…

Research in physics teaching has supported the use of analogies as an effective instructional tool that can be used to facilitate students' understanding of physics concepts. The effectiveness of analogies lies in that they allow students to form cognitive links between what they already know and what they are learning, harmoniously integrating,…

The success of films such as "Avengers: Endgame," "Black Panther," and "Captain Marvel" has established the superhero genre in modern popular culture. Many students will have seen these films, or at the very least they are familiar with a number of the superhero characters. In the physics classroom, content based on…