Even though many physics teachers take their students on a calculation adventure through circular motion and Newton's universal law of gravity to determine Earth's velocity, most of us leave it at that. We present the final result and say, "Look, Earth is moving around the Sun at about 107,000 km/hr (66,000 mph), yet we can't feel the motion…

A popular introductory physics laboratory experiment is one focusing on Snell's law. This is straightforward to complete with lasers and prisms, but here we present an alternative version that guides the students through some of the major historical developments, recreating and analyzing significant experiments. The discovery of Snell's law has a…

In many introductory physics classes, diffraction of light is introduced first, then more advanced diffraction topics such as x-ray diffraction, Bragg's law, and crystallography are covered. Since using x-rays raises safety concerns and atomic spacing in a crystal is not easy to change, microwaves with macroscopic crystals have been used to study…

Fermat's principle states that a light ray refracted across different media will traverse the fastest path as the physics for Snell's law. A geometric proof of Fermat's principle will be demonstrated as an intuitive approach to learn high school geometry and physical optics. It will be proved explicitly by showing that all alternative paths need…

In recent years, with the more powerful functions of smartphones, the use of sensors integrated by mobile phones as an auxiliary tool for physical experiment teaching has become more popular. Combined with the related mobile phone apps, people easily can develop and expand the physical experiment contents of mechanics, optics, acoustic phenomena,…

This paper describes an alternative approach to teaching and learning practices in an undergraduate physics laboratory. The instructor plans and implements the 5E instructional model into the laboratory instruction. The article includes an example of the 5E lesson for the laboratory component of a physics course, which has separate lecture and…

Light polarization, which is the direction of electromagnetic field oscillation, provides information that is highly different from that of spectral and intensity images and thus can enhance various fields of optical metrology. Polarization imaging can be also used by combining polarization and imaging, thereby providing polarization and spatial…

Understanding reflection and refraction are an integral part of school and college learning. In nature even birds and fish (Archer fish) very skillfully use refraction to strike down prey present above or below the water surface. Fermat's principle allows one to look beyond the reasons behind the laws governing the reflection and refraction. A…

In 1849, Hippolyte Fizeau determined the speed of light in a famous experiment. The idea was to measure the time taken for a pulse of light to travel between an intense light source and a mirror about 8 km away. A rotating cogwheel with 720 notches, that could be rotated at a variable speed, was used to chop the light beam and determine the flight…

Background: The development of context-based science curricula has been identified as one of the most effective curricular innovations to develop interest and better conceptual understanding of many areas in science. However, such a curriculum can be more fruitful if it starts with the assessment of learners' contextualized knowledge about the…

Lens imaging is a classic topic in physics education. To guide students from their holistic viewpoint to the scientists' analytic viewpoint, an image-based approach to lens imaging has recently been proposed. To study the effect of the image-based approach on undergraduate students' ideas, teaching experiments are performed and evaluated using…

We demonstrate how the form of a plano-convex lens and a derivation of the thin lens equation can be understood through simple physical considerations. The basic principle is the extension of the pinhole camera using additional holes. The resulting images are brought into coincidence through the deflection of light with an arrangement of prisms.…

In the present article, the context-dependency of student reasoning is studied in a context of optics. We investigated introductory students' explanations about the behavior of light when different light sources, namely a small light bulb and a laser, were used in otherwise identical task assignments. The data was gathered with the aid of pretest…

Physics textbooks often present items of disciplinary knowledge in a sequential order of topics of the theory under instruction. Such presentation is usually univocal, that is, isolated from alternative claims and contributions regarding the subject matter in the pertinent scientific discourse. We argue that comparing and contrasting the…

A goldfish isn't always visible inside its fishbowl. If the fish gets sufficiently close to the bowl glass, it will disappear for certain angles of observation. In a recent paper in this journal, Zhu and Shi explained the effect in terms of total internal reflection. We show in what follows that the phenomenon involves some richer optics: a…