We will present a problem-solving method for the dynamics of a projectile that has two perpendicular acceleration vectors through rotation of the axes. This methodology of reparameterizing the two-dimensional system simplifies the speed optimization calculus.

Resistor--capacitor (RC) circuit labs help students, but most courses don't include them because of complications and cost. This work presents an easy and inexpensive Arduino-based lab on the charge and energy transfer between two capacitors with different values of the initial electric charge when they are connected through a resistor. Capacitors…

The motion of a bead along a path restricted to straight lines (restricted brachistochrone), sliding without friction from rest and accelerated by gravity, is considered. For two shapes of path, the geometry of the route optimized to provide the least travel time from one point to another is obtained. The bead's travel times, path lengths, and…

Students often find the study of electrostatics to be abstract, heavily mathematical, and non-intuitive. This paper describes an inquiry-based approach to teaching electrostatics in an introductory calculus-based physics class that emphasizes the primacy of student conceptual understanding.

North Korea's development of nuclear weapons and, more recently, intercontinental ballistic missiles (ICBMs) has added a grave threat to world order. The threat presented by these weapons depends critically on missile range, i.e., the ability to reach North America or Europe while carrying a nuclear warhead. Using the limited information available…

There are many reasons for an instructor to consider using social media, particularly in a large introductory course. Improved communications can lessen the sense of isolation some students feel in large classes, and students may be more likely to respond to faculty announcements in a form that is familiar and comfortable. Furthermore, many…

We report the combined use of Wikispaces (wikis) and collaborative group problem solving (CGPS) sessions conducted in introductory-level calculus-based physics classes. As a part of this new teaching tool, some essay-type problems were posted on the wiki page on a weekly basis and students were encouraged to participate in problem solving without…

Interactive lecture demonstrations (ILDs) are a powerful tool designed to help instructors bring state-of-the-art teaching pedagogies into the college-level introductory physics classroom. ILDs have been shown to improve students' conceptual understanding, and many examples have been created and published by Sokoloff and Thornton. We have used the…

A coin tossed onto a table often ends up rolling in such a way that the center of mass remains approximately stationary. Although this phenomenon has been studied for many years and is well-documented in the literature, it is perhaps not widely appreciated in the physics education community that the motion can be understood without the use of…

In the usual treatment of waves in introductory courses, one begins with traveling waves and the frequency/wavelength relationship f[lambda] = v, where "v" is the wave velocity. One then makes the point about superposition and shows that two waves traveling in opposite directions can add up to a standing wave; Eq. (1) still applies. This approach…

Several years ago I had to select a new textbook for my calculus-based introductory physics class. I subscribe to Just-in-Time Teaching methods,1 which require students to read the book before the material is covered in class. Thus, the readability of the text by the students is critical. However, I did not feel that I was the best judge of this…

An exercise that gives students a chance to use the equations of state for both an ideal gas and for an adiabatic process in determining the points at which heat flow reverses direction and at which the working substance reaches its maximum temperature is demonstrated. (KR)