AAPT Logo
AJP Logo
 
   
 

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

Feb 2003

Volume 71, Issue 2, pp. 103-192

back to top
RSS Feeds

The disorder metaphor

Ralph Baierlein and Clayton A. Gearhart

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 103

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable
Show PACS
05.70.Ce Thermodynamic functions and equations of state

Errors in Goldstein’s Classical Mechanics

Martin Tiersten

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 103 | Cited 3 times

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable
Show PACS
01.30.Vv Book reviews
01.50.-i Educational aids
47.00.00 Fluid dynamics

Authors’ Reply

John L. Safko and Charles P. Poole, Jr.

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 103

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable
Show PACS
01.50.-i Educational aids
45.30.+s General linear dynamical systems
back to top
RSS Feeds

Oersted Medal Lecture 2002: Reforming the mathematical language of physics

David Hestenes

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 104 | Cited 25 times

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The connection between physics teaching and research at its deepest level can be illuminated by physics education research (PER). For students and scientists alike, what they know and learn about physics is profoundly shaped by the conceptual tools at their command. Physicists employ a miscellaneous assortment of mathematical tools in ways that contribute to a fragmentation of knowledge. We can do better! Research on the design and use of mathematical systems provides a guide for designing a unified mathematical language for the whole of physics that facilitates learning and enhances physical insight. This research has produced a comprehensive language called geometric algebra, which I introduce with emphasis on how it simplifies and integrates classical and quantum physics. Introducing research-based reform into a conservative physics curriculum is a challenge for the emerging PER community. Join the fun! © 2003 American Association of Physics Teachers.
Show PACS
01.50.-i Educational aids
01.55.+b General physics
back to top
RSS Feeds

Resource Letter: PEs-1: Physical eschatology

Milan M. Ćirković

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 122 | Cited 4 times

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This Resource Letter treats the nascent discipline of physical eschatology, which investigates the future evolution of astrophysical objects, including the universe itself, and is thus both a counterpart and a complement to conventional cosmology. While sporadic interest in these topics has flared up from time to time during the entire history of humanity, a truly physical treatment of these issues has only become possible during the last quarter century. This Resource Letter deals with these recent developments. It offers a starting point for understanding what the physical sciences might say about the future of our universe and its constituents. Journal articles, books, and web sites are provided for the following topics: history and epistemology of physical eschatology, the future of the Solar system, the future of stars and stellar systems, the global future of the universe, information processing and intelligent communities, as well as some side issues, like the possible vacuum phase transition and the so-called Doomsday Argument.© 2003 American Association of Physics Teachers.
Show PACS
01.30.Rr Surveys and tutorial papers; resource letters
98.80.-k Cosmology
01.50.-i Educational aids

Characterizing the performance of baseball bats

Alan M. Nathan

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 134 | Cited 14 times

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The characterization of the performance of baseball bats is presented from a physics point of view. The goal is to define a set of laboratory measurements that can be used to predict performance in the field. The concept of a model-independent collision efficiency, which relates the post-collision ball speed to the initial ball and bat speeds, is introduced and its properties are investigated. It is shown to provide a convenient link between laboratory and field measurements. Other performance metrics are presented, related to the collision efficiency, and evaluated according to their predictive power. Using a computational model, it is shown that bat performance depends on the interplay of the elasticity of the ball–bat collision, the inertial properties of the ball and bat, and the bat swing speed. It is argued that any method of determining performance needs to take all of these factors into account. A new method is proposed and compared with commonly used existing methods. © 2003 American Association of Physics Teachers.
Show PACS
01.55.+b General physics
45.40.-f Dynamics and kinematics of rigid bodies

Mechanics of the surf skimmer revisited

Takeshi Sugimoto

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 144 | Cited 1 time

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The mechanics of the surf skimmer, fun sport at the beach, is re-examined by using fundamental fluid mechanics. Comparison of the existing theories and consideration of the effects previously neglected lead to the conclusion: Edge’s model is physically incorrect; Tuck and Dixon’s theory provides physical insights into the surf skimming; there are several trade-offs in the mechanics of the surf skimmer and these make this sport fun and challenging. © 2003 American Association of Physics Teachers.
Show PACS
01.55.+b General physics
47.90.+a Other topics in fluid dynamics (restricted to new topics in section 47)
45.90.+t Other topics in classical mechanics of discrete systems (restricted to new topics in section 45)

The physics of stone skipping

Lydéric Bocquet

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 150 | Cited 3 times

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The motion of a stone skimming over a water surface is considered. A simplified description of the collisional process of the stone with water is proposed. The maximum number of bounces is estimated by considering both the slowing down of the stone and its angular stability. The conditions for a successful throw are discussed. © 2003 American Association of Physics Teachers.
Show PACS
01.50.-i Educational aids
45.40.Gj Ballistics (projectiles; rockets)
01.55.+b General physics

Experiences with the magnetism of conducting loops: Historical instruments, experimental replications, and productive confusions

Elizabeth Cavicchi

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 156 | Cited 4 times

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This study investigates nineteenth century laboratory work on electromagnetism through historical accounts and experimental replications. Oersted found that when a magnetic needle was placed in varying positions around a conducting wire, its orientation changed: in moving from a spot above the wire to one below, its sense inverted. This behavior was confusing and provocative. Early experimenters such as Johann Schweigger, Johann Poggendorff, and James Cumming engaged it by bending wire into loops. These loops, which increased the magnetic effect on a compass placed within, also provided evidence of their understanding and confusion. Coiling conducting wires around iron magnetized it, but when some wires coiled oppositely from others, the effect diminished. This effect confused contemporaries of Joseph Henry who made electromagnets, and amateurs later in the century who constructed multisection induction coils. I experienced these confusions myself while working with multilayer coils and induction coils that I made to replicate the historical instruments. This study shows how confusion can be a productive element in learning, by engaging learners to ask questions and invent experiments. By providing space for learners’ confusions, teachers can support the development of their students’ physical understandings. © 2003 American Association of Physics Teachers.
Show PACS
01.50.-i Educational aids
41.20.-q Applied classical electromagnetism

The equivalence principle and the bending of light

Rafael Ferraro

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 168 | Cited 1 time

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The apparent discrepancy between the bending of light predicted by the equivalence principle and its corresponding value in general relativity is resolved by evaluating the deflection of light with respect to a direction that is parallel transported along the ray trajectory in 3-space. In this way the bending predicted by the equivalence principle is fulfilled in general relativity and other alternative metric theories of gravity. © 2003 American Association of Physics Teachers.
Show PACS
01.50.-i Educational aids
04.00.00 General relativity and gravitation

The hydrogen atom in electric and magnetic fields: Pauli’s 1926 article

Galliano Valent

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 171 | Cited 6 times

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The results obtained by Pauli in his 1926 article on the hydrogen atom made essential use of the dynamical so(4) symmetry of the bound states. Pauli used this symmetry to calculate the perturbed energy levels of an hydrogen atom in a uniform electric field (Stark effect) and in uniform electric and magnetic fields. Although the Stark effect in hydrogen has been studied experimentally, Pauli’s results in mixed fields have been studied only for Rydberg states of rubidium atoms in crossed fields and for lithium atoms in parallel fields. © 2003 American Association of Physics Teachers.
Show PACS
01.50.-i Educational aids
32.60.+i Zeeman and Stark effects
42.50.-p Quantum optics

Bernoulli levitation

Chris Waltham, Sarah Bendall, and Andrzej Kotlicki

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 176 | Cited 2 times

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Bernoulli levitation is the basis of many popular counter-intuitive physics demonstrations. However, few of these lend themselves to a quantitative description without recourse to computational fluid dynamics. Levitation of a flat plate is the exception, and we present an analysis that illustrates several principles of fluid mechanics in a pedagogically useful way. © 2003 American Association of Physics Teachers.
Show PACS
01.50.-i Educational aids
47.10.-g General theory in fluid dynamics
back to top
RSS Feeds

Note on thermal heating efficiency

E. T. Jaynes

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 180 | Cited 5 times

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Kelvin showed the maximum efficiency with which heat can be converted into work; but there is a dual theorem about the maximum efficiency with which heat at one temperature can be converted into heat at another temperature. It has some surprising implications, in particular that the efficiency with which we heat our buildings could in principle be improved by a large factor. This long known, but still little known, fact is of current pedagogical interest and practical importance. © 2003 American Association of Physics Teachers.
Show PACS
01.50.-i Educational aids
05.70.-a Thermodynamics

Comment on “The hidden symmetry for a quantum system with an infinitely deep square-well potential,” by Shi-Hai Dong and Zhong-Qi Ma [Am. J. Phys. 70 (5), 520–521 (2002)]

Asim Gangopadhyaya and Jeffry V. Mallow

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 182

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
© 2003 American Association of Physics Teachers.
Show PACS
01.50.-i Educational aids
03.65.Fd Algebraic methods
02.20.-a Group theory
03.65.Ge Solutions of wave equations: bound states
back to top
RSS Feeds

A low-cost scanning Fabry–Perot cavity for laser experiments

T. T. Grove

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 184 | Cited 1 time

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
© 2003 American Association of Physics Teachers.
Show PACS
01.50.Pa Laboratory experiments and apparatus
42.60.Da Resonators, cavities, amplifiers, arrays, and rings

Center of mass correction to an error-prone undergraduate centripetal force experiment

Peter Ronhovde and Rudy Sirochman

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 185

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this undergraduate laboratory experiment we measure the centripetal force acting on a bob in uniform circular motion. As the experiment was originally designed, it consistently yielded large errors due to a subtle twist of the bob as the mass was increased incrementally. This error is due to the fact that the center of mass changes relative position as the mass is incremented; therefore, the spring that provides the centripetal force for the apparatus causes an unintended torque on the bob. A solution to the problem consists of positioning the incremental masses so that the center of mass does not change position. This simple correction provides a useful lesson on redesigning an undergraduate laboratory experiment to obtain better agreement with theory. © 2003 American Association of Physics Teachers.
Show PACS
01.50.Pa Laboratory experiments and apparatus
07.10.Pz Instruments for strain, force, and torque
06.60.Sx Positioning and alignment; manipulating, remote handling
back to top
RSS Feeds

Hydrogen: The Essential Element

John S. Rigden, Author and James O’Connell, Reviewer

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 189

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable
Show PACS
01.30.Vv Book reviews

Radiation: At Home, Outdoors and in the Workplace

Dag Brune, Author, Ragnar Hellborg, Author, Bertil R. R. Persson, Author, Rauno Pääkkönen, Author, and Jacob Shapiro, Reviewer

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 189

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable
Show PACS
01.30.Vv Book reviews

An Introduction to Stochastic Processes in Physics

Don S. Lemons, Author and Vinay Ambegaokar, Reviewer

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 191

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable
Show PACS
02.50.Ey Stochastic processes
01.55.+b General physics
02.50.Fz Stochastic analysis
01.30.Rr Surveys and tutorial papers; resource letters

Contemporary Physics and the Limits of Knowledge

Morton Tavel, Author and Alan S. Thorndike, Reviewer

American Journal of Physics -- February 2003 -- Volume 71, Issue 2, pp. 191

Online Publication Date: Jan 2003

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable
Show PACS
01.30.Vv Book reviews
Close

Your Recent History Recent History Help

Recently Viewed

  1. How to hit home runs: Optimum baseball bat swing parameters for maximum range trajectories
  2. Heat capacity in bits
  3. Phase transition-like behavior in a low-pass filter
  4. From Cbits to Qbits: Teaching computer scientists quantum mechanics
  5. Entangled photons, nonlocality, and Bell inequalities in the undergraduate laboratory

AAPT on:

close