They say that there is no such thing as a stupid question. In a pedagogically pure sense, that's probably true. But some questions do seem to flirt dangerously close to being really quite ridiculous. One such question might well be, "How many dimensions of space are there?" I mean, it's pretty obvious that there are three:…

This paper examines the notion of laws in chemistry. Vihalemm ("Found Chem" 5(1):7-22, 2003) argues that the laws of chemistry are fundamentally the same as the laws of physics they are all "ceteris paribus" laws which are true "in ideal conditions". In contrast, Scerri (2000) contends that the laws of chemistry are…

On October 14,2012, Felix Baumgartner, an Austrian sky-diver, set some new world records for his discipline. Jumping from a height of about 39 km, he reached a top speed of 1342 km/h, becoming the first human being to break the sound barrier in free fall. In order to understand some essential physics aspects of this remarkable feat, we wonder why…

In popular accounts of the time dilation effect in Einstein's special relativity, one often encounters the statement that moving clocks run slow. For instance, in the acclaimed PBS program "NOVA," Professor Brian Greene says, "[I]f I walk toward that guy... he'll perceive my watch ticking slower." Also in his earlier piece for The New York Times,…

For those in the profession of teaching physics who reside in or plan to visit the Los Angeles area, I would highly recommend a trip to the Huntington Library in San Marino, specifically to a permanent exhibit entitled "Beautiful Science: Ideas that Changed the World" in the Dibner Hall of the History of Science. The exhibit contains…

A science video blog, which has gone viral, shows a wooden block shot by a vertically aimed rifle. The video shows that the block hit dead center goes exactly as high as the one shot off-center. (Fig. 1). The puzzle is that the block shot off-center carries rotational kinetic energy in addition to the gravitational potential energy. This leads a…

This activity is designed to illustrate an application of resistive forces in the introductory physics curriculum with an interdisciplinary twist. Students are asked to examine images of riverbed boulders after a flood and estimate the water flow that was needed to push the boulders downstream. The activity provides an opportunity for students to…

Education Research in Indonesia has begun to lead to the development of character education and is no longer fixated on the outcomes of cognitive learning. This study purposed to produce character education based general physics learning model (CEBGP Learning Model) and with valid, effective and practical peripheral devices to improve character…

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…

The expansion or compression of gas confined in a piston-and-cylinder device is a classic working example used for illustrating the First and Second Laws of Thermodynamics. The balance of energy and entropy enables the estimation of a number of thermodynamic properties. The entropy generation (also called entropy production) resulting from this…

The trebuchet has quickly become a favorite project for physics and engineering teachers seeking to provide students with a simple, but spectacular, hands-on design project that can be applied to the study of projectile motion, rotational motion, and the law of conservation of energy. While there have been free trebuchet simulators and range…

Student difficulties in science learning are frequently attributed to misconceptions about scientific concepts. We argue that domain-general perceptual processes may also influence students' ability to learn and demonstrate mastery of difficult science concepts. Using the concept of center of gravity (CoG), we show how student difficulty in…

This paper deals with a brief history of the most remarkable Euler numbers "e,"?"i"?and?"?" in mathematical sciences. Included are many properties of the constants "e,"?"i"?and?"?" and their applications in algebra, geometry, physics, chemistry, ecology, business and industry. Special…

In the second paper of this series, the effect of transverse femoral stresses due to locomotion in theropod dinosaurs of different sizes was examined for the case of an unchanging leg geometry. Students are invariably thrilled to learn about theropod dinosaurs, and this activity applies the concepts of torque and stress to the issue of theropod…

In a previous article we demonstrated that a simple, passive external circuit incorporating a thermistor, connected to a mobile device through the headset jack, can be used to collect temperature data. The basic approach is to output a sine wave signal to the headset port, through the circuit, and input the resulting signal from the headset…