摘要:

The Ritz theory of electromagnetism and optics is criticized in relation to the experimental evidence after the introduction of a simple and natural modification of the hypothesis concerning the velocity of radiation scattered by the electrons of a medium. It is argued that the theory is then in harmony with the electron theory of dispersion, accounts satisfactorily for aberration, the first-order Doppler effect from moving sources and interferometer experiments on binary stars. There is no evidence from binary stars which contradicts it. It is compatible with the second-order Doppler effect and possibly the Fizeau experiment since arguments are advanced which indicate that these phenomena depend essentially on the momentum and energy of radiation. Other phenomena are discussed. It is concluded that the best evidence against the theory comes from experiments on the lifetimes of fast mesons and the velocity of γ rays and light from moving sources. The justifications for the discussion are the desirability of having the experimental base of an important part of physics be as rigorous as possible, and the hope that it sharpens our understanding of existing evidence for special relativity and stimulates new and different experiments.

ISSN:0002-9505    

DOI:10.1119/1.1971219

出版商:American Association of Physics Teachers    

年代:1965

数据来源: AIP

摘要:

A simple type of apparatus has been developed for measuring the specific heat of a gas at constant volume with an accuracy of about 10%. A large capacitance is used to supply a known amount of energy to a known amount of gas and the momentary rise of the gas pressure is recorded. With a suitable choice of time constant the results are highly reproducible and the calculated specific heats of air and argon are close to accepted values.

ISSN:0002-9505    

DOI:10.1119/1.1971214

出版商:American Association of Physics Teachers    

年代:1965

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1971217

出版商:American Association of Physics Teachers    

年代:1965

数据来源: AIP

摘要:

The elastic scattering of spinless particles from a spherically symmetric stationary target is considered. The main idea is to describe the incident beam of particles as a certain statistical ensemble of one-particle wave packets, and to define the differential cross section in terms of the average scattering of the particles in this ensemble. The physical significance of this mode of description is discussed, and arguments are presented as to why it should be regarded as a realistic description of typical scattering experiments. The discussion is general, and not restricted to potential scattering. It is based on the notion of theSmatrix, and the most basic ideas of theSmatrix are discussed. A simple derivation of the partial wave expansion is given within the framework ofSmatrix theory.The aim of this paper is mainly pedagogical, and the final results obtained are old and well established.

ISSN:0002-9505    

DOI:10.1119/1.1971221

出版商:American Association of Physics Teachers    

年代:1965

数据来源: AIP

摘要:

Some experiments in nuclear quadrupole resonance suitable for the undergraduate laboratory or senior project are described. The Zeeman splitting of resonance lines and the effect of solid phase transitions may be readily observed with simple apparatus.

ISSN:0002-9505    

DOI:10.1119/1.1971223

出版商:American Association of Physics Teachers    

年代:1965

数据来源: AIP

摘要:

The radial equation for the hydrogen atom problem is factored to yield raising and lowering operators for the oribtal angular momentum quantum numberl. This procedure, which is a direct analog for the usual treatment of the angular momentum operators, is considered to offer many pedagogical advantages for an introductory course in quantum mechanics over the usual series method of solution. The raising process is terminated by establishing the existence of an upper bound forl. The use of the hypervirial relations is advocated for displaying such an a priori upper bound.

ISSN:0002-9505    

DOI:10.1119/1.1971225

出版商:American Association of Physics Teachers    

年代:1965

数据来源: AIP

摘要:

The paths of light rays reflected or refracted at spherical surfaces are obtained by application of Fermat's principle. The first-order Gaussian equations describing the image-forming properties of such surfaces are derived and the criteria for image formation are discussed.

ISSN:0002-9505    

DOI:10.1119/1.1971227

出版商:American Association of Physics Teachers    

年代:1965

数据来源: AIP

摘要:

A building of about 134 000-sq ft area, containing research rooms, shops, store rooms, three lecture halls, classroom, and offices, for the Departments of Physics and of Mathematics has been completed at Kansas State University. Details concerning the construction, the provision of laboratory facilities, and special features of the building are given, as are floor plans and statements of costs involved.

ISSN:0002-9505    

DOI:10.1119/1.1971229

出版商:American Association of Physics Teachers    

年代:1965

数据来源: AIP

摘要:

An undergraduate experiment is described in which Schlieren photographs are made of the sound waves produced by an electric spark. Electronic control of the time lapse between initiation of the sound pulse and the xenon flash tube illumination allows observation of the wavefronts at various stages of their progress through air or of their reflection from curved surfaces. A method of determining the velocity of sound in air is described.

ISSN:0002-9505    

DOI:10.1119/1.1971230

出版商:American Association of Physics Teachers    

年代:1965

数据来源: AIP

摘要:

The relativistic theory of collisions of macroscopic particles is developed from the two axioms of energy conservation and relativity, by use of standard relativistic kinematics (without, of course, assuming the mathematical expression for relativistic energy). We derive, in turn, the equivalence of rest-mass and rest-energy, the usual mathematical expression for the total energy in terms of the rest-energy, the conservation of 3-momentum, and the equivalence of total energy with inertial mass. We incidentally find all possible conservation laws of quantities described by the product of a scalar with a function of the speed.

ISSN:0002-9505    

DOI:10.1119/1.1971232

出版商:American Association of Physics Teachers    

年代:1965

数据来源: AIP