摘要:

A number of qualitative and quantitative fluorescence x−ray experiments were performed by junior and senior level physics students using a relatively inexpensive radioactive disk x−ray source and a chamber which was constructed by students. The chamber is described in detail and results of several experiments are shown. Students gained experience with sample preparation techniques, x−ray excitation and detection, analysis and interpretation of data, programming of a small calculator, machine shop techniques, and applied physics experiments.

ISSN:0002-9505    

DOI:10.1119/1.10081

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

The lowest possible angle of validity of the Rutherford scattering formula is determined on the basis of a simple hypothesis. The corresponding impact parameter is then obtained and related to the distance between scattering nuclei that would exist if the scattering foil could be compressed into a single layer of atoms arranged in a square array.

ISSN:0002-9505    

DOI:10.1119/1.9847

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

It is shown that very simple iteration routines for solving a very broad class of transcendental equations, including many of great importance in physical applications, can be developed and used quite conveniently with pocket calculators such as the Hewlett−Packard HP−35 and others of similar capability. Questions of convergence and methods of extending domains of convergence are discussed. While the methods considered are not new to mathematicians and computer scientists, it does not seem to be generally appreciated that they may be so easily and systematically used with machines of this class. While it is true that some repetitive key punching is required, this is not usually very tedious; the solution of most equations is accomplished with the ease (and within the time span) of typing a three or four line paragraph on a typewriter, once the routine is developed. Some of the procedures considered can also be used for the solution of systems of simultaneous transcendental equations. The methods which are used are extremely convenient and practical when a few or even a few dozen transcendental equations are to be solved. If there are a few hundred, however, it is probably best to use the IBM 360!

ISSN:0002-9505    

DOI:10.1119/1.9848

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

We present a simplified derivation of approximate solutions for the magnitude of, and the relations between, the three critical fields of a type II superconductor done in the spirit of the Ginzburg−Landau equations. The appearance of an unexpected equation restricting the free choice of macroscopic parameters is shown to be a direct consequence of the ’’correctness’’ of the Ginzburg−Landau theory, i.e., its physical equivalence to the microscopic theory of Bardeen, Cooper, and Schrieffer.

ISSN:0002-9505    

DOI:10.1119/1.9849

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

Laboratory learning modules are self−teaching modules designed to enable a student to learn a measurement technique and familiarize himself with measurement instrumentation independently of a laboratory course. A module developed to help students to learn how to measure electrical resistance is described. The equipment and facility requirements for setting up learning modules are outlined and a list of other laboratory learning modules which have been developed is presented.

ISSN:0002-9505    

DOI:10.1119/1.9850

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

The Schwirian Science Support Scale has been utilized to study the attitude toward science and its interrelationship to society of a broad cross section of nonscience students. In spite of the development of a counterculture antagonistic toward science, this study indicates that these students appear to accept those societal values important for the support of science.

ISSN:0002-9505    

DOI:10.1119/1.9851

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

We analyze the thermodynamics of a simple heat engine. The engine’s efficiency is calculated for an idealized but reasonable model. The engine’s work cycle is compared with a Carnot cycle, and it is shown to be equivalent to the Carnot cycle as an extremely ideal limiting case. A working model of the engine is easily constructed for classroom demonstrations. We measured the force law parameters for a working model, and we estimate the efficiency of this model. The estimated efficiency of our demonstration engine is small compared with that of a Carnot engine operating at the same temperatures. We show that a Carnot engine could in principle be constructed based on the thermal expansion concept, but its efficiency would be intrinsically small when rubber is the working substance because of the inherently small incremental temperature increase possible in an adiabatic expansion.

ISSN:0002-9505    

DOI:10.1119/1.9852

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

A personalized course in thermodynamics is described which organizes learning about moderately difficult projects designed to bring a sense of continuity and relevance to student studies. The approach minimizes formal lecturing and tries to encourage discovery and enjoyment in learning. Student lecturing, laboratory visits, and demonstrations, along with class discussions of projects, are used as a replacement for most, but not all, formal classroom lecturing. Student comments are used as a basis for evaluating the approach.

ISSN:0002-9505    

DOI:10.1119/1.9853

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.10082

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.10083

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP