In this article, we describe a simple method which can be used to measure the efficiency of a low power dc motor, a motor-converted dynamo and a coupled motor-dynamo module as a function of the speed of rotation. The result can also be used to verify Faraday's law of electromagnetic induction. (Contains 1 table and 8 figures.)

The periodic table and the periodic system are central to chemistry and thus to many introductory chemistry courses. A number of existing activities use various data sets to model the development process for the periodic table. This paper describes an image arrangement computer program developed to mimic a paper-based card sorting periodic table…

Several case studies from popular television medical dramas are described for use in an undergraduate biochemistry course. These cases, which illustrate fundamental principles of biochemistry, are used as the basis for problems that can be discussed further in small groups. Medical cases provide an interesting context for biochemistry with video…

Science is a dynamic discipline, representative of the nature of science. Yet, young science students continue to think everything is already discovered. In this study, we examine why students are not actively doing science. From professional development to student engagement, how are classrooms and students changing as we increase teachers'…

Societal benefit depends on the general public's understandings of biotechnology (Betsch in "World J Microbiol Biotechnol" 12:439-443, 1996; Dawson and Cowan in "Int J Sci Educ" 25(1):57-69, 2003; Schiller in "Business Review: Federal Reserve Bank of Philadelphia" (Fourth Quarter), 2002; Smith and Emmeluth in "Am Biol Teach" 64(2):93-99, 2002). A…

Evidence exists that children's understanding can be facilitated through collaborative group work with peers, but little is known about the underlying processes. When processes are discussed, they are typically assumed to involve the assimilation of superior ideas that are constructed jointly. However, the assimilation of joint constructions…

The cooling of objects is often described by a law, attributed to Newton, which states that the temperature difference of a cooling body with respect to the surroundings decreases exponentially with time. Such behaviour has been observed for many laboratory experiments, which led to a wide acceptance of this approach. However, the heat transfer…

When data with and without an optically active sample are acquired simultaneously while one manually rotates the analyser, the graph of the first signal versus the second one is an ellipse whose shape shows the phase shift between the two signals; this shift is twice the optical rotation. There is no need to measure the rotation of the analyser or…

A common example of real-world motion that can be modeled by a differential equation, and one easily understood by the student, is the simple pendulum. Simplifying assumptions are necessary for closed-form solutions to exist, and frequently there is little discussion of the impact if those assumptions are not met. This article presents a…

An undergraduate organic chemistry experiment demonstrating real-life application of GC-MS to arson accelerant identification is described. Students are given the task of comparing a sample recovered from a "crime scene" to that from a "suspect's clothing". Accelerants subjected to different conditions are recovered using a quick and simple…

Rapid technological enhancements and changes necessitate people who can understand the relation between science and technology and perceive as well as comment on technological enhancements. The aim of the present study was to determine physics students comprehension of the operation principles of wired telephone, mobile phone, and latest medical…

For the case of objects thrown from an elevated position, students tend to believe an object thrown at an upward angle will always land farther away than one thrown horizontally at the same speed. That this is not always the case comes as a great surprise to many. By analysing the situation of a horizontally-thrown object outdistancing one thrown…

A whiplash event is a relative motion between the head and torso that occurs in rear-end automobile collisions. In particular, the large inertia of the head results in a horizontal translation relative to the thorax. This paper describes a simulation of the motion of the head and neck during a rear-end (whiplash) collision. A head-neck model that…

One of my favorite 19th century electrical scientists is Edward Weston, and one of my favorite devices for teaching the topics of electromagnetic forces and torques is the D'Arsonval galvanometer. The junction of these two topics is Weston's improved meter movement that has been used in analog meters for the past 125 years.

This past semester I brought a Lava Lite[R] Lamp into my classroom. Why bring such a thing into class? Many of today's students are part of the "retro" movement. They buy clothes from the '60s, they wear their hair like people did in the '60s, and they look for the ideals and themes related to living in the 1960s. Physics education reform is also…