Many high school and first-year university courses include discussion of the magnetic effect of currents. Frequently discussed textbook examples include long, straight wires, circular current loops, and solenoids, partly because these examples are tractable mathematically. The solenoid naturally leads to discussion on magnetic materials since it…

The photoelectric effect is one of the key experiments taught during first- or second-year university and high school modern physics courses. It is usually the first experiment to introduce light quantization and the concept of photons as "packets of energy." Here, we want to point out a widespread mistake concerning the interpretation…

Students are exposed to a variety of unrealistic physical experiences seen in movies, video games, and short online videos. A popular classroom activity has students examine footage to identify what aspects of physics are correctly and incorrectly represented. Some of the physical phenomena pictured might be tricks or illusions made easier to…

Ask a typical high school student to draw a picture of how a bar magnet works and most of the drawings produced will show a "+" and "-" sign at the two ends. Some students will write "N" and "S." If you then ask some follow-up questions, they will often resort to talking about "charges" being responsible for the magnetism. For several years, I…

In 1879, in the midst of the debate between English and continental scientists about the nature of cathode rays, William Crookes conducted an experiment in which a small mill or "paddle wheel" was pushed along tracks inside a cathode ray tube (CRT) (similar to that shown in Fig. 1) when connected to a high-voltage induction coil. Crookes…

Heat transfer is widely taught in secondary Earth science and physics. Researchers have identified many misconceptions related to heat and temperature. These misconceptions primarily stem from hunches developed in everyday life (though the confusions in terminology often worsen them). Interactive computer simulations that visualize thermal energy,…

Expands upon the popular belief that mirrors cause the left-right reversal of objects placed in front of them. The image-location rule and image-symmetry rule are applied throughout the article to help summarize some important properties of mirror images. (ZWH)

Describes the Capacitor-Aided System for Teaching and Learning Electricity (CASTLE) project which is a high school electricity curriculum developed by high school and college physics teachers. The project is motivated by research on students' conceptual difficulties in electricity. The instructional materials developed allow students to challenge…

Describes high-speed photographic methods used to demonstrate that the tip of a snapped towel does break the sound barrier. (ZWH)

Describes an experiment designed to disprove the belief that an electrical field originating from a point inside a closed conducting surface cannot produce an electric field outside this surface. (ZWH)

Listed are errors students make by accepting misconceptions about pressure and precautions teachers might take to avoid fostering those misconceptions. Misconceptions discussed include pressure as a measure of energy per unit volume, fluid flow only from high to low pressure, and the lack of pressures lower than a vacuum. (CW)

Discussed is the importance of using scale drawings in teaching physics. Concepts including the orbit of the Space Shuttle, the smoothness of the earth's surface, the oblateness of the earth, the eccentricity of the earth's orbit, and the solar system are illustrated. (CW)

Describes an interactive computer program (RelLab) that acts to introduce the fundamental ideas of relativity to students. Students working cooperatively investigate paradoxes of relative motion by constructing thought experiments and discussing their findings. (ZWH)

Described are the results of a conceptual physics survey given to a small group of high school physics students with the goal of identifying common misconceptions held by students. Three common misconceptions were identified and are discussed in detail. (CW)

Discusses some incorrect representations of electric fields in textbooks. Considers total charge or charge density and two- or three-dimensional diagrams. (YP)