bluuebunny/crossref_metadata_2025 huggingface dataset:
Management styles and professional identities among UK podiatrists
Authors: Blakeman Paul D.
Published: April 2003

Interviews and observation of NHS state‐registered chiropody (podiatry) has been used to study the effects of NHS reforms on professional identity, which inevitably yielded information on management processes. This paper adapts and expands Hood's interpretation of Douglas's grid/group cultural theory model. Here it is expanded into a three‐dimensional model to reflect on local managers attitude to regulation; strength of allegiance to different stakeholder groups; and to the level of monitoring and accountability. This expanded model can be used in management evaluation by categorising attitudes in high‐order hierarchist, entrepreneurialist, covert fatalist or pseudo‐egalitarianist management trends. A manager drawn from a profession who identifies with the core professional ethos resents increased measures of monitoring and accountability retreating to the regulatory frameworks, pointing to inconsistencies between those of the organisation and the profession. Other profession based managers less inclined to worry about regulatory frameworks were more prepared to monitor staff often presenting a pseudo‐egalitarian environment where talk of “empowering” left staff feeling less empowered.
The art and science of fireworks
Authors: Bianco Blake , Willis Courtney
Published: April 2003

Those awe-inspiring shows of colorful explosives and combustibles known as pyrotechnics are a marvelous blend of chemistry, physics, and the aesthetic value of colored light and intense sound. The experience of author Bianco in assisting with the execution of an electronically fired show, in which some 584 pyrotechnic devices were detonated, prompted a talk at the 2000 AAPT Winter Meeting and this note.
Using the GPS to determine the size of Earth
Authors: Biermann Mark L. , Nelson Nicholas A.
Published: April 2003

A simple experiment allows students to determine the radius of Earth using a Global Positioning System receiver. The experiment gives excellent results and allows students to explore mathematical analysis, random and systematic errors, and the distinction between accuracy and precision.
Case-study experiments in the introductory physics curriculum
Authors: Arion D. N. , Crosby K. M. , Murphy E. A.
Published: April 2003

Carthage College added inquiry-based case study activities to the traditional introductory physics laboratory. Student teams designed, constructed, and executed their own experiments to study real-world phenomena, through which they gained understanding both of physic principles and methods of physics research. Assessment results and student feedback through teacher evaluations indicate that these activities improved student attitudes about physics as well as their ability to solve physics problems relative to previous course offerings that did not include case study.
Students view symbol confusion
Authors: Giammarino Jason
Published: April 2003

Why are students with high grades on the tests written by their own physics teachers doing significantly poorer on standardized tests? Might there be a flaw in the standardization?
Newton’s second law for systems with variable mass
Authors: Chandler David
Published: April 2003

Rockets and other systems with variable mass require a modification of the usual form of Newton’s second law. When a rocket is the prototype system, the derivation involves a confusing mixture of positive and negative terms. An alternative prototype system is proposed that simplifies the derivation by making all terms positive.
Laser ranging
Authors: Haddad Ra’ad M.
Published: April 2003

This paper shows a new and simple idea to measure distances using a laser pointer, which can be built from simple materials.
Flight of the bagel
Authors: Singh Kanwal
Published: April 2003

Pre-college students investigated various aspects of acceleration due to gravity using bagels, video cameras, and a lot of imagination. Using very simple equipment, they were able to explore many issues related to designing an experiment and taking measurements, as well as having a lot of fun.
A teacher’s dream
Authors: Decker C. Eugene , Badger Norman W.
Published: April 2003

Steven Chu, recipient of the 1997 Nobel Prize in physics, graduated from Garden City High School on Long Island, New York, in 1966. The question naturally arises in any teacher’s mind: “Is there something special about a Nobel prizewinner’s early preparation?” We were at Garden City High School those three decades ago, along with Tom Miner, and we participated in a superior teaching environment.
Meteorological pressure-sensor inaccuracies
Authors: Gallagher Frank W. , Fredrickson Sherman E.
Published: April 2003

The (incorrect) use of an atmospheric pressure sensor can cause errors on the scale of pressure changes caused by real meteorological events such as the passage of thunderstorms and tornadoes. A simple experiment is described that illustrates the potential errors that can arise from improper use of a quality pressure sensor.
Equitable teaching of physics to women students: Thoughts for the new decade
Authors: Norby Rena Faye
Published: April 2003

This note describes the author’s experience as a woman student and instructor in the field of physics. She provides suggestions for ensuring equitable teaching of women physics students in high school and college classes.
How big is a planet?
Authors: McIntosh Gordon
Published: April 2003

A calculation is presented to estimate the lower limit for the radius of a spherical body. This limit is one of the criteria generally suggested to determine whether or not a body in the solar system should be considered a planet.
Teaching astronomy through the news media
Authors: Shipman Harry
Published: April 2003

Why are big science ideas like the big-bang theory accepted as true? Science demands that evidence be used to support its claims; however, as we sometimes seek to cram more and more content into our courses, we often forget that teaching scientific habits of mind is as important as teaching the subject. In this column, I describe an effective teaching technique that uses news media stories to help students see the importance of evidence.
An analemma experiment
Authors: Davis Dan M.
Published: April 2003

I describe here a very simple experiment that allows a science class to measure the latitude of their school, determine the inclination of the Earth’s axis to the ecliptic, and demonstrate the noncircularity of our orbit around the Sun. The only tools needed are: something tall and pointed (a flagpole will do), paint and a paint brush, a tape measure, a watch, and an accurate way of finding the time (such as a radio).
Using wireless keypads in lecture classes
Authors: Burnstein Ray A. , Lederman Leon M.
Published: April 2003

Experience using a wireless keypad system for five years in class rooms is discussed. This system is designed to increase student participation. The data can be displayed to students quickly and/or saved. The system is flexible and can accommodate a wide variety of teaching styles.
For love of teaching
Authors: Hubisz John L.
Published: April 2003

What is it that turns otherwise reasonable individuals into physics teachers? I really don’t know, but after listening to colleagues’ stories over the years, I see that many of us came into the profession via rather unique routes — a mathematical physicist who failed algegra, a graphic artist who sought better answers, a novice biology teacher required to teach physics who stuck with it — and each one of us has a story to tell.
Linking physics, humanities, and social sciences
Authors: Carstens-Wickham Belinda
Published: April 2003

Southern Illinois University Edwardsville won funding from the federal interagency competition, Leadership Opportunity in Science and Humanities Education, which supported interdisciplinary courses combining the natural sciences and the humanities. The author analyzes her experiences developing a very successful and popular interdisciplinary course, entitled “The Atomic Era,” which features a unique combination of physics, sociology and German studies taught jointly by a physicist, a sociologist, and a Germanist. The objectives of the course, the laboratories and demonstrations, instructional goals, !!assignments, organization, testing, student and faculty assessment, expenses, and the special challenges of coordinating three faculty members and a wide variety of topics and perspectives are addressed and analyzed.
Springbok: The physics of jumping
Authors: Dufresne Robert J. , Gerace William J. , Leonard William J.
Published: April 2003

The physics of jumping is explored for a simple spring-loaded toy. The toy is easy to make and easy to analyze using an elementary Hooke’s law model. Possible uses in introductory physics are described. Conceptual and pedagogical issues are discussed
Teaching an online physical science course
Authors: O’Connell James
Published: April 2003

This note is a discussion of some of the details of how a lecture-demonstration classroom course was modified to be given as a World Wide Web course at a community college. The advantages of convenience for the students and the use of web resources are weighed against the disadvantages of the loss of face-to-face discussion and problem solving and the replacement of demonstration experiments with Java applets.
Full immersion into physics
Authors: Lattery Mark , Cicerelli Marc , Covach Erin , Dempsey Steve , Franke John , Rudich Carrie , Smith Michelle
Published: April 2003

This article describes the use of student-led small group research projects, as a teaching strategy, in the context of a college-level physical science course. Tips for guiding such projects and project examples are given.
An Astronomy Angulator™
Authors: Zeilik Michael
Published: April 2003

As I have refined my conceptual astronomy course, I have been struck by the major confusion exhibited by students on the topic of angles. People intuit that smaller angular size means greater distance, but rarely apply this knowledge to actual events, in part because they cannot easily measure angles. To assist in naked-eye observations, I devised a simple and inexpensive device to measure small angles.
Absorption of microwaves in the microwave oven
Authors: Wardle D. A.
Published: April 2003

A microwave oven is used to demonstrate that, in comparison to liquid water, both ice and liquid nitrogen are almost completely transparent to microwaves. The difference in transparency is also simply explained.
The magic magnifier
Authors: Andereck Barbara , Secrest Sherri
Published: April 2003

An inexpensive magnifier with an extended tube that enables clear images to be readily seen can be constructed from PVC pipe and small converging lenses. Students can calculate the design parameters and predict the magnification.
Report on a study of middle school physical science texts
Authors: Hubisz John L.
Published: April 2003

Several physical science textbooks used in the middle schools in 1998 were examined in critical detail to determine if the perception that the textbooks were rife with errors was indeed true. We have found that it is indeed true and that none of the books examined were suitable for middle school students from several perspectives.
The dual function of sand on a clay tennis court
Authors: Cross Rod
Published: April 2003

A simple experiment is described that explains why sand on a tennis court increases friction between the ball and the court but it reduces friction on shoes, allowing players to slide more easily.
Unstable rotation of rigid bodies in empty space
Authors: Wardle D. A.
Published: April 2003

The torque-free rotation of an asymmetric top about one principal axis is unstable. The unstable motion has the interesting feature that the apparent direction of rotation periodically reverses. This is described together with a simple apparatus for its observation.
Technology as a teaching tool
Authors: Blanton Patricia
Published: April 2003

From day one, new physics teachers are flooded with messages about how to teach the material, deal with students and parents, navigate the political “waters” of a school, effectively assess what students are learning, and balance the time required to accomplish these tasks effectively.
Good days, bad days
Authors: Mamola Karl
Published: April 2003

We teachers have a great deal in common. And I don’t mean just physics teachers; I mean teachers of all subjects at all levels. What brings this to mind is a story told not long ago by Kay McSpadden, a columnist for the Charlotte Observer and a high school English teacher.
Demonstration experiments with platform scales
Authors: Mainardi Raúl T.
Published: April 2003

This paper describes simple demonstrations that can be performed using either one of two inexpensive spring scales. Having large, easy-to-read dials, such scales may be easily read by students even in a large classroom.
“Physics for the rest of us”
Authors: Chiaverina Chris
Published: April 2003

I think that most physics teachers would agree the world is a much more interesting place and their lives are richer because of their awareness and understanding of physics.
Apparent wave motion in decorative fabric
Authors: Wardle D. A.
Published: April 2003

Some decorative fabrics constitute a large number of identical harmonic oscillators arranged in a line. The oscillators can move in such a way as to create the illusion of wave motion. By studying this counter example, students gain insight into the nature of wave motion.
Sliding off a roof: How does the landing point depend on the steepness?
Authors: van den Berg Willem H. , Burbank Andrea R.
Published: April 2003

It is simple to measure the landing point of an object sliding off a rough, elevated ramp, as a function of the angle of inclination of the ramp. The results can be predicted straightforwardly using the work-energy theorem and projectile motion. There is excellent agreement between the data and the highly nonlinear but quite intuitive theoretical curve.
Seeing rectifiers at work
Authors: Pomarico Juan A.
Published: April 2003

In the present work, a very simple circuit is presented that illustrates the principal characteristics of current rectification. To this end, LEDs are used in a rectification circuit instead of normal diodes to “see” if they are in conduction or not.
Some examples of centripetal acceleration
Authors: Bryan Ronald
Published: April 2003

In lecturing to undergraduate students at Texas A&M University over the years, I have either come across or thought of problems in centripetal acceleration that I assign in an effort to make the subject more interesting. Here are four of my favorites.
Matrix optics for the secondary classroom
Authors: Larabee Dave
Published: April 2003

Using matrices we can find the path that a light beam will take through glass, lenses, mirrors, etc. First though we have to somehow describe these light rays.
An aerodynamicist's view of Lift, Bernoulli, and Newton
Authors: Eastlake Charles N.
Published: April 2003

The production of lift by airfoils is a popular topic but one accompanied by unneeded controversy. Both Bernoulli’s law and Newton’s laws describe lift production correctly. The proper application of them is described from the perspective of an aerodynamicist.
Marking sense of students' answers to multiple-choice questions
Authors: Dufresne Robert J. , Leonard William J. , Gerace William J.
Published: April 2003

A detailed example is used to illustrate the difficulties making sense of students’ answers to multiple-choice questions. We explore how correct answers can be false indicators of student knowledge and understanding. We caution against excessive reliance on multiple-choice questions for instructional decisions.
Three books on mathematical physics
Authors: Hubisz John L. , Roeder John L.
Published: April 2003

Three books on mathematical physics
Unconventional Dynamo
Authors: Dindorf Wojciech
Published: April 2003

About 10 years ago I encountered one of the most remarkable dynamos I have ever seen. It was produced by Philip Harris. The major component is a magnet in the form of a cylinder having one pole on the outside and the other on the inside.
Using the Work-Energy Theorem with Car and Driver Website Data
Authors: Velázquez-Avilés Angel Luis
Published: April 2003

The physics class usually presents concepts that can be taught by means of laboratories, but may still leave students with no idea of how these concepts can be related to real-life situations. This note discusses how to use the velocity-versus-time data from the Car and Driver website to show the relationship between velocity and other kinematic and dynamic quantities.
Another Way to Demonstrate Lenz’s Law
Authors: Zhang Chang Geng , Hu Shi Feng
Published: April 2003

Many ways of demonstrating Lenz’s law to introductory-level physics students have been described in the literature. We have found another such demonstration that is both simple and highly effective.
Prevent Burnout — Add Fuel to Your Fire
Authors: Blanton Patricia
Published: April 2003

The first few years of teaching can be both difficult and rewarding. Perhaps as you approach the end of your first year, you are looking for encouragement and methods to improve some aspect of your teaching.
Aiming a 730-km long neutrino beam
Authors: Frank J. , Serifovic M. , Stewart J. , Holbrow C. H.
Published: April 2003

A plan to send a neutrino beam through the Earth provides an interesting context in which to present the problem of calculating the displacement vector between two geographic locations.
The Hard Drive: an Experiment for Faraday’s Law
Authors: Hinaus Brad , Veum Mick
Published: April 2003

An introductory laboratory experiment for the study of Faraday’s Law has been created using the computer hard drive as the focus. Students learn how data is stored magnetically, and then with the aid of a scaled-up model of the hard drive, students read their stored data using a solenoid, computer, and knowledge of Faraday’s Law.
The Force Table; Historical Variants
Authors: Greenslade Thomas B.
Published: April 2003

The force table is a very old piece of experimental apparatus, dating back to the beginning of the 18th century. However, the phenomena of physics stay the same, no matter how old the design of the apparatus. This note gives two historical variants on the standard force table setup.
Interfacing Microcomputers: Back to the Future
Authors: De Jong Marvin
Published: April 2003

This article gives a brief (and somewhat incomplete) history of the role of microcomputer interfacing as it pertains to introductory physics teaching. A new approach to interfacing is described, and several interfacing examples are given.
Five-Minute Vector Analysis Exercise
Authors: Halada Richard
Published: April 2003

To introduce vector analysis methods, three students lift a roll of masking tape suspended by strings. The forces are read from force gauges connected to the strings, while the directions are quickly captured with a three-ruler “fan.” The forces are then drawn to scale on the board for further analysis.
More or Less than Half Full?
Authors: Gardner Martin
Published: April 2003

Physics Trick of the Month problem is to ask why a capped bottle that seems to be about half full of water is hard to measure. The bottle has a long neck, making it difficult to know for sure exactly whether the water fills more than half of the bottle’s volume, less than half, or exactly half.
Our Referees
Authors: Marnola Karl
Published: April 2003

Many teachers at all levels — high school, college, and university — share their time and expertise with The Physics Teacher by serving as manuscript referees. Articles and notes appearing in TPT have been reviewed by at least one referee who has examined the submitted manuscript and assessed its suitability for publication in our journal.
Microwave Mischief and Madness
Authors: Hosack Heather , Marler Nathan , MacIsaac Dan
Published: April 2003

We briefly describe the general function of standard commercial microwave ovens, together with instructions and photos of several amusing, sometimes pyrotechnic demonstrations.
Colliding Magnetic Pendula: When Is a Collision Not Collision-like?
Authors: Kagan David , Gaffney Chris
Published: April 2003

Even though the Newtonian Demonstrator and the MagnaSwing appear to be similar devices, their motions are dramatically different. The reasons are explained in this note.
Speed of Sound in Gases Using an Ultrasonic Motion Detector
Authors: Pettersen Inge H. A.
Published: April 2003

An ultrasonic sonar system determines the distance to a body by measuring the time interval from the time a sound pulse is sent out until the instant of time the reflected pulse from the body is received. Here are experiments to determine the speed of sound in other gas mixtures and temperature variations of the speed of sound in air.
Muons in the Classroom
Authors: Mühry Henry , Ritter Patrick
Published: April 2003

We present an unusual classroom experiment in particle physics at an introductory level for high school or college students. Students investigate high energy particles from cosmic radiation and measure the lifetime of cosmic muons. The experiment uses surplus material given away from physics research institutes.
Measurement and Analysis of the Field of Disk Magnets
Authors: Connors Martin
Published: April 2003

An inexpensive magnetic-field sensing chip that gives direct readout in volts may be used to make a sensor for laboratory use. We describe how to make the sensor and give examples of its use in verifying the expression for the on-axis field of disk magnets.
A Linear/Rotational Motion Exercise with a Tape Deck Counter
Authors: Chalmers Joseph S.
Published: April 2003

The reading of the counter on an audio tape deck or VCR is proportional to the number of rotations of the take-up reel but not to the elapsed time that the tape has been playing. We derive the relation between the counter reading and the elapsed time from elementary considerations. The problem is an illustrative example of the relation between linear and rotational motion in a device with which students are very familiar
A Useful Multipurpose Instrument
Authors: Dindorf Tomasz , Dindorf Wojciech
Published: April 2003

A Ping-Pong ball bearing is an interesting and easy-to-make physical instrument that can be used for demonstrations as well as for making measure ments.1 Take a bicycle spoke or a similar straight steel wire and sharpen it at one end using a file. Then take a Ping-Pong ball and pass the spoke through its center. Find something like an eggcup that has only a slightly larger diameter than the ball. Fill it up to the top with water and place the ball on it. Balance the wire by sliding it delicately through the ball one way or the other.
A Paper Pistol
Authors: Gardner Martin
Published: April 2003

In his diary, Lewis Carroll speaks of making what he called paper pistols for his child friends. The pistol is best folded from a single sheet of newspaper as shown in the illustration. When held at one corner and swung rapidly through the air, a portion of the paper pops out with a loud bang.
Teaching with Physlets®: Examples From Optics
Authors: Dancy Melissa , Christian Wolfgang , Belloni Mario
Published: April 2003

Physlets are scriptable Java applets that can be used for physics instruction. In this article we discuss the pedagogical foundations of Physlet use and provide a sample of Physlet-based exercises that could be used to teach optics.
Radiometer Mystery
Authors: Dindorf Wojciech
Published: April 2003

The author has a radiometer that is about 80 years old that he uses in demonstrations for various audiences. When exposed to light, the “fan” turns very fast, then slows down, and eventually comes to rest. But when I touch the glass with my hand, the whirling starts again. Sometimes, before restarting, the fan turns in the opposite direction for awhile. Why?
The Mechanic’s Electromagnet
Authors: Stacey James E.
Published: April 2003

A demonstration of electromagnetism as used in retrieving lost objects.
A spotlight to the stars
Authors: McCarthy Thomas K.
Published: April 2003

I have found the use of a lantern-sized flashlight to be an ideal pointer under skies that one would classify as relatively dry.
Zero gravity physics
Authors: Gardner Martin
Published: April 2003

Here’s a simple way to demonstrate that gravity vanishes inside a freely falling container.
The revolving circle
Authors: Gardner Martin
Published: April 2003

Make a top with a white cardboard circle and a pencil. Draw a black circle on the disk. Can you guess what you will see when the top is spun?
Three switches puzzle
Authors: Gardner Martin
Published: April 2003

Three on-off switches are on the wall of a first floor. Two switches are dummies, not connected to anything. How do you know which switch is connected to a bulb?
Rotating cylinders
Authors: Gardner Martin
Published: April 2003

This physics trick involves only two toilet-paper tubes and a can.
Four hearts
Authors: Dindorf Wojciech
Published: April 2003

This article describes a trick with four paper hearts hanging in a doorway and the way they are oriented.
Resonating blow-pipe drum
Authors: Haws LaDawn
Published: April 2003

Here is one way to construct an inexpensive, easy-to-make demonstration of resonance.
Magic jigger
Authors: Gardner Martin
Published: April 2003

To make this novelty, you will need a thick-sided glass jigger (shot glass) with a cone-shaped interior.
Logarithmic Scales: A Useful Example
Authors: Bartlett Albert A.
Published: April 2003

Logarithmic intensity scales are widely encountered in astronomy (star magnitudes), acoustics (decibels), seismology (the Richter scale), and elsewhere. Yet students often have difficulty mastering the concept of logarithmic scales. With this note, I am calling attention to a case of the application of a logarithmic scale to something that is simple, transparent, and widely understood. The simplicity of the example is such that it will allow the merits and use of logarithmic scales to be more easily grasped by students. The understanding of this simple logarithmic scale can then be applied to the comparison of sound intensities.
Warning! Objects in Mirror Are Closer Than They Appear
Authors: Libertun Ariel R.
Published: April 2003

Devices familiar to students are always good examples to illustrate physics concepts. I have found the right-side mirrors of cars to be one of these illustrative devices, especially because of the mysterious label printed on them: Warning! Objects in mirror are closer than they appear. Finding the physical reason for the label is a very interesting exercise that may be used to review or introduce some optical concepts.
Work Reworked
Authors: Jordan R. G.
Published: April 2003

Students often encounter some difficulties with work and potential energy using the approaches given in most introductory physics texts. For instance, one difficulty that occurs is associated with the question “What is the work done in lifting a book (of mass m) from the floor onto a table through a vertical distance h?”
Women in Physics: A High School-College Interaction
Authors: Light Kelly , Todd David , DeHart Laura , Day Michael
Published: April 2003

In this note we describe a successful interaction between our two high schools and college that addressed, in a local way, the underrepresentation of women in our physics programs.
All I Need To Know About Teaching I Learned from My Students
Authors: Galus Pam
Published: April 2003

The term “edutainment” has been coined to describe activities that both educate and entertain. Physics provides many opportunities for this approach and Pamela Galus, an 11-year veteran of the Omaha Nebraska Public Schools system, has a passion for creating situations where students can have fun learning. Pam is currently teaching astronomy, physics, and biology, and has authored two books and approximately 100 educational articles. Share in her lessons learned from students.
Physics in the Art Museum
Authors: Dale Daniel A. , Bailey Brenae L.
Published: April 2003

Parisian artist Paul Signac met the impressionists Claude Monet and Georges Seurat in 1884. Their influence spurred his work in pointillism (or, where the juxtaposition of small dots of color in conjunction with the limited resolving power of the human eye lead to the impression of color coalescence).1–4 To stimulate a cross-disciplinary appreciation of science and art, we used the University of Wyoming Art Museum's Signac painting “Barques de Pêche à Marseilles” (see Fig. 1) to explore diffraction theory and the anatomical limitations to our vision during an optics exercise done in the museum.
Simple Uncertainty-Principle Experiment
Authors: Sawicki Charles A.
Published: April 2003

Recent discussions in TPT have considered the pros and cons of an early introduction of students to modern physics.1–4 In this regard, appropriate experiments with classical waves can help students understand some important but counterintuitive aspects of modern physics. I recently taught a summer course that introduced high school seniors who had graduated with some background in physics and algebra to aspects of quantum physics and relativity. In this paper I'll describe a simple experiment I used to introduce these students to uncertainty principles in quantum physics.
Analyzing Collisions in Terms of Newton's Laws
Authors: Roeder John L.
Published: April 2003

Although the principle of momentum conservation is a consequence of Newton's second and third laws of motion, as recognized by Newton himself,1 this principle is typically applied in analyzing collisions as if it is a separate concept of its own. This year I sought to integrate my treatment of collisions with my coverage of Newton's laws by asking students to calculate the effect on the motion of two particles due to the forces they exerted for a specified time interval on each other. For example, “A 50-kg crate slides across the ice at 3 m/s and collides with a 25-kg crate at rest. During the collision process the 50-kg crate exerts a 500 N time-averaged force on the 25 kg for 0.1 s. What are the accelerations of the crates during the collision, and what are their velocities after the collision? What are the momenta of the crates before and after collision?”
Lifetimes of Incandescent Bulbs
Authors: Menon V. J. , Agrawal D. C.
Published: April 2003

An article by Leff1 on incandescent bulbs has been very successful in illuminating the minds of not only physics students but also teachers. It has also prompted many articles that explore various aspects of incandescent lamps.2–9 An interesting topic discussed by Leff concerns lifetime statistics of bulbs by drawing analogy from radioactive decay of nuclei. Leff obtained an empirical formula for the survival probability of commercial bulbs and also hinted at the approximate equality of the half-life, the average life, and the most probable life of the same. While teaching this topic over the past few years, we found that the students were confused about the precise link between the survival and decay probabilities, and were also unable to derive the said equality of different lives as this problem was left in Ref. 1 as an exercise. The aim of this paper is to clarify these ideas.
A Physics Teacher in Europe
Authors: Nickell Duane S.
Published: April 2003

Last summer, I had the good fortune of winning a fellowship to take a scientific tour of Europe.1 My goal was to learn more about the people whose work I have studied and taught throughout my professional career — scientists like Galileo, Newton, and Einstein, whose work has revealed the beauty, grandeur, and comprehensibility of the universe. Below, I list and describe some of the highlights of my trip. The four cities listed are among those commonly visited by tourists.
Redesigned Air-Column Resonance Apparatus
Authors: Singh Gurbax , Graf Erlend H.
Published: April 2003

This paper describes a redesigned air-column resonance apparatus1 that offers several advantages over the traditional one.2 It does away with water or the long rod to vary the length of the air column. Instead a specially designed piston is moved inside a plastic or glass tube by external magnets to vary the length of the air column. Plastic tubes of various sizes are commercially available,3 but we salvaged one from an old commercial resonance apparatus. The tube has 2.85-cm inner and 3.15-cm outer diameter, respectively. The redesigned resonance apparatus can be operated in either the horizontal or the vertical position.
Specular Reflection from a Rough Surface
Authors: Fakhruddin Hasan
Published: April 2003

The rough surface of a ground glass plate generally gives a diffuse reflection. However, if light from an object is incident on it at a low enough grazing angle, the rough surface behaves like an optically plane surface and causes specular reflection of the incident light, producing a reflected image of the object. A reflected image is obtained from the rough surface of a ground glass plate.
Optical Property of the Ellipse Derived from Energy Conservation
Authors: Sztrajman Jorge , Rela Agustín
Published: April 2003

It is well known that rays of light originating at one of the foci of an elliptical mirror converge at the other focus after reflecting off the surface.1 Usually this is proven using the equation of the ellipse and geometrical theorems2 or by means of calculus.3 In this paper we show that the proof may be done very easily by considering a simple mechanical system having the same geometry and using conservation energy.
Action Research to Evaluate Student Achievement
Authors: Blanton Patricia
Published: April 2003

How do you know if your students are really learning the concepts you are presenting? Data from assessments help answer the question but what data do you examine? Is the information best found in the overall class average on tests, the number of students who did not score at a “passing” grade, how well the grades fit a bell curve, or how many students scored C or better? Teachers and administrators look at these statistics to determine the effectiveness of instructional strategies and student achievement. High-stakes testing uses overall scores as the determining factor for assigning credit to students, determining promotion or retention, allowing acceptance into programs or institutions, and evaluating the overall effectiveness of instructional practice. Yet composite scores alone do not address the question about which concepts the students are mastering. Specific data are needed to identify the problem areas and determine the approaches to best help students achieve mastery.
Trinity sure—I
Authors: Swartz Cliff
Published: April 2003

We’ve been reviewing introductory physics texts lately. One of my quibbles has to do with the teaching of Newton’s three laws. What concerns me is that many texts seem to trivialize these. This is the first of three editorials on this topic.
Position of objects floating in a glass
Authors: Teague Harold J.
Published: April 2003

A popular demonstration often used when discussing surface tension involves a less-dense object (cork, etc.) floating on a liquid surface (water) in a container (glass). For a number of years I have used a variation of this demonstration which suggests that the relative position of the floating object is due to a combination of the surface-tension properties of water and gravitational forces.
Teaching physics with the Peace Corps in Fiji
Authors: Ellisen Raleigh
Published: April 2003

The author was a Peace Corps volunteer teacher for two years at a high school in Fiji. The educational system and physics curriculum are described. Some of the author’s experiences teaching in a different country conclude the article.
Cheap and easy coupled-oscillations demonstration
Authors: Sawicki Charles A.
Published: April 2003

A suspended magnetic dipole undergoes torsional oscillations in the Earth’s magnetic field. The length of the suspending string is adjusted so that the pendulum periods equals that for torsional oscillations and energy exchange between these modes is observed.
Using counterintuitive problems in teaching physics
Authors: Campanario Juan Miguel
Published: April 2003

In this article I suggest the use of problems that yield a solution that challenges students’ expectations or are worded in such a manner that students obtain a wrong solution by making some obvious mistakes. The counterintuitive result or the wrong result is supposed to point out the inadequate initial analysis and subsequent solving method. Some examples of these two kinds of problems are provided and discussed.
Trinity sure—II
Authors: Swartz Clifford E.
Published: April 2003

What could be simpler? Exert a force on a mass, and it accelerates. F=ma! You can work that formula into any number of problems about objects on inclined planes, or Atwood's machine, or blocks sliding along a surface with coefficient of friction, μ.
Pictorial representation of torque and rotational inertia
Authors: Bird Robert W.
Published: April 2003

Here is a brief analysis I like to show my physics students when we start rotational dynamics. It introduces the concepts of torque and rotational inertia in a somewhat natural way.
The Rosse telescope
Authors: Greenslade Thomas B.
Published: April 2003

In 1845 the Third Earl of Rosse built a telescope with a 6-ft metal mirror on his estate in Birr in Ireland. What was the largest telescope in the world until 1918 has recently been restored to working condition.
Period and amplitude
Authors: Akridge Russell
Published: April 2003

Three simple demonstrations illustrate small amplitude, periodic systems displaying amplitude-dependent periods. Physics students enjoy observing such demonstrations, and from them they learn that small amplitude is not sufficient to guarantee that period is independent of amplitude.
Finite rotations
Authors: Bolina Oscar , da Silva Neto J. A.
Published: April 2003

We discuss two basic properties of angular displacements, namely, the anticommutation of finite rotations, and the commutation of infinitesimal rotations, and show how commutation is achieved as the angular displacement gets smaller and smaller.
Feeling forces that produce torques
Authors: Bracikowski Christopher
Published: April 2003

The classic introductory physics laboratory experiment used to study the static equilibrium of a rigid body can easily be modified to allow students to actually feel forces that produce torques acting on the body. This sensory experience helps students develop an intuitive understanding of torque.
Force exerted by a falling chain
Authors: van den Berg Willem H.
Published: April 2003

The force exerted by a vertically falling chain being brought to rest on a horizontal surface can be measured as a function of time using “off-the-shelf” hardware and software. The results confirm the prediction based on impulse and momentum considerations.
Temperature distribution in a microwave oven
Authors: Viiri Jouni
Published: April 2003

Some years ago Steyn-Ross and Ridell reported how they had studied the standing waves in a microwave oven. The pictures in the 1990
Optical properties of double-glazed windows
Authors: Robinson Paul B.
Published: April 2003

There I was in my reading chair for the first time in a new house and while looking out the window was unsettled to notice not one but two virtual images. This itself wasn’t so suprising since I knew the window was double glazed; instead, it was that the two images had different sizes. Why should this be?
Practically perfect in every way
Authors: Swartz Clifford E.
Published: April 2003

Thanks to the computer, our experimental work is now free of errors. Free at last. Can it really be so? A measurement without error is like a painting without a frame. It might be a great picture, but you wouldn’t hang it in your living room.
The 100-meter dash: Theory and experiment
Authors: Wagner Glenn
Published: April 2003

This note outlines the theory regarding the position and velocity associated with the 100-m dash. The theory is applied to data produced by world-class sprinters as well as students with little formal training in sprinting. Inexpensive computer software is used to analyze the data to verify the outcome of these races so as to comment on the accuracy of the theory.
Physics on a rotating reference frame
Authors: Johns Robert H.
Published: April 2003

This note describes some insights into relative motion and the Coriolis force not available from a computer or by watching apparatus on a lab bench. They are better seen and experienced as a participant. The apparatus is a 5-m-long rotating frame of reference made from two 8-ft-long plywood carts that can be used in a classroom or lab if the regular furniture is movable or in a hall, commons area, or cafeteria.
Don’t the texts have it wrong?
Authors: Webb Jerry
Published: April 2003

Here is a problem that, in my opinion, all the texts have wrong. A common amusement-park show consists of a cyclist riding his motorcycle around the inside of a vertical cylinder.
The annual pumpkin drop
Authors: Kagan David
Published: April 2003

We reenact the legendary Tower of Pisa experiment of Galileo Galilei every Halloween using pumpkins. Some logistics and some physics of this escapade are discussed.
Falling and orbiting
Authors: Stewart Maurice Bruce
Published: April 2003

Two particles in circular orbits around their mutual center of mass, if arrested in their orbital motion and falling from rest, will come together in a time equal to 1/(42) of the period of their former revolution.
Another use for the sonic ranger
Authors: Kernohan James C.
Published: April 2003

A new use for the sonic ranger in the high school physics lab is presented. The computer and sonic ranger allow students to see phenomena heretofore unseen.
Baking a magnetic-field display
Authors: Cavanaugh Terence , Cavanaugh Catherine
Published: April 2003

Copy machine developer powder is an alternative for creating permanent displays of magnetic fields. A thin layer of developer powder on a sheet of paper placed over a magnet can be baked in the oven, producing a lasting image of a magnetic field.
A real look at speeds and stopping distances
Authors: Malone Jim , Holzwarth Dave
Published: April 2003

Students should be provided with an opportunity to see if doubling the speed of a car really does make the stopping distance four times as big. This lab exercise provides such an opportunity.
The first mechanical clock and its primitive escapement
Authors: Crane H. Richard
Published: April 2003

In nosing around in an antique shop on Third Avenue in New York City long ago, I found a clock that (they said) came in with a shipment from Brazil. The clock uses the principles of the first of the mechanical clocks to appear, which was in about 1360 AD—some historians say this is earlier.
Celebrating a centennial—Leo Szilárd (1898–1964)
Authors: Stinner Arthur
Published: April 2003

In the long list of gifted Hungarian scientists and mathematicians active in the first half of this century, the name of Leo Szilárd rises to the top. This year we celebrate the centennial of his birth.
Computer technologies and the phenomenon of refraction
Authors: Helfgott Michel
Published: April 2003

Fermat’s principle implies the well-known law of refraction of light. Our purpose is to show how one can give a simple justification, using only basic coordinate geometry, with the help of a graphics calculator and the Geometer’s Sketchpad®.
Physics of volleyball: Spiking with a purpose
Authors: Behroozi F.
Published: April 2003

A few weeks ago our volleyball coach telephoned me with a problem: How high should a player jump to “spike” a “set” ball so it would clear the net and land at a known distance on the other side of the net?
Constant acceleration and kinetic friction
Authors: Piatek Slawomir , Gautreau Ronald
Published: April 2003

Simple experiments illustrating important physical principles are precious. Here is one showing the ideas of constant acceleration and kinetic friction.
Vector treasure hunt
Authors: Widmark Stephen
Published: April 2003

High school physics students learn the vector concept by participating in a “treasure hunt.”
A problem of relative, constrained motion
Authors: Bollina Oscar , Parreira J. Rodrigo
Published: April 2003

We develop a simple method to determine the acceleration of a mass relative to a moving wedge on which the mass slides down.
The hydrostatic paradox: Simple geometries, explicit calculations
Authors: Walker James S.
Published: April 2003

The hydrostatic paradox is one of those fascinating topics that can elicit a truly interactive discussion with a class. In this paper, we show that by considering containers with simple geometries we can explore the paradox with explicit calculations, even at the algebra level.
Images of the Seattle Space Needle in raindrops
Authors: Lapp David R. , Bristow Ben
Published: April 2003

This paper describes the optics principles present in a newspaper photograph of the Seattle Space Needle; the optics of the image was incorrectly described in the caption.
Do-Ahead Event: The Pringle Caper
Authors: Bouffard Karen
Published: April 2003

In this second Physics Olympics column, we present a staple of many Olympics competitions—a “Do-Ahead” experiment that is prepared in the classroom and brought to the Olympics. “The Pringle Caper” was designed by Steve Cremer, physics teacher from the Braintree (Massachusetts) high school. We include one such activity at each Eastern Massachusetts Physics Olympics meet. Among other pluses, the “Do-Ahead” allows students who are unable to travel to the Olympics to participate.
Just sixty years ago
Authors: Bartlett Albert A.
Published: April 2003

In a George Washington University building is a large bronze plaque with the following inscription: “In this room, January 26, 1939, Niels Bohr made the first public announcement of the successful disintegration of uranium into barium with the attendant release of approximately two hundred million electron volts of energy per disintegration.” This note recounts the story.
Tossing a garden hose
Authors: Greene Nathaniel R.
Published: April 2003

When a section of a garden hose is tossed and thus accelerated, the flow rate is observed to change. Newton’s second law is invoked to help explain the fluid dynamics of this phenomenon.
Using transits for astronomy activities
Authors: McIntosh Gordon
Published: April 2003

The combination of a transit mounted on a tripod provides a very flexible apparatus for measuring angles in astronomy laboratory activities. These activities can include measurements of horizon coordinates (azimuth and altitude), equatorial coordinates (right ascension and declination), and a measurement of the angular velocity of Earth. Other activities can also be developed based on this apparatus.
Using space to teach physics
Authors: Stern David P.
Published: April 2003

This article describes a new educational resource, a book-sized site on the World Wide Web covering astronomy, Newtonian mechanics, and spaceflight.
Guest editorial: Revitalizing Physics
Authors: Kirkpatrick Larry D.
Published: April 2003

Why is there suddenly such widespread interest in revitalizing physics? More than five hundred physics educators applied to attend last year’s conference “Building Undergraduate Physics Programs for the 21st Century.” While serving as a discussion leader, I learned that the major concern was declining enrollments. In discussing reasons for the decline, I was reminded of many beliefs about physics education that are simply taken on faith.
Terminal velocity
Authors: Herbert Steven , Toepker Terrence
Published: April 2003

Authors re-examine Paul Hewitt’s question in a past “Figuring Physics”: When a Ping Pong ball dropped from the top of a high building reaches terminal speed, its acceleration is zero. Now suppose the ball is projected upward with an initial speed greater than this terminal speed. At the instant its speed equals this terminal spped on the way up, what is the magnitude of its acceleration?
Golden oldie: Black sack atoms
Authors: Pennington Kevin
Published: April 2003

Here is a time-tested activity designed to help students better understand early experimental work on the structure of the atom. It’s a variation on the popular “black box” challenge.