摘要:

Working directly from the impulse-momentum theorem in combination with the angular-momentum equation, Rutherford's formula is derived without making explicit use of the trajectories of the scattered particles. This derivation is noteworthy in that it specifically demonstrates the special nature of the inverse-square-law force in classical scattering theory.

ISSN:0002-9505    

DOI:10.1119/1.1933969

出版商:American Association of Physics Teachers    

年代:1955

数据来源: AIP

摘要:

Demonstration lectures for high school pupils are effective in stimulating some to choose careers in physics and in giving many an increased appreciation of physics. This institution has sponsored a diversified program of physics lectures for large groups during the past five years. The results of this experience are described, and an evaluation of the program is presented.

ISSN:0002-9505    

DOI:10.1119/1.1933970

出版商:American Association of Physics Teachers    

年代:1955

数据来源: AIP

摘要:

A formula for the angle which produces maximum range of a projectile in vacuum on a spherical, nonrotating earth is derived. Initial velocities and altitudes are assumed to be such that the projectile returns to the earth.

ISSN:0002-9505    

DOI:10.1119/1.1933971

出版商:American Association of Physics Teachers    

年代:1955

数据来源: AIP

摘要:

Academic origins of 1137 Fellows of the American Physical Society are studied and academic eminence is investigated.

ISSN:0002-9505    

DOI:10.1119/1.1933972

出版商:American Association of Physics Teachers    

年代:1955

数据来源: AIP

摘要:

This paper describes an experiment which investigated laboratory achievement of Naval Academy midshipmen, working singly, in pairs, and in quartets. No significant differences in the means of the three groups were found on two laboratory tests. The quartet groups had significantly higher laboratory grades, based on reports written in the laboratory.

ISSN:0002-9505    

DOI:10.1119/1.1933973

出版商:American Association of Physics Teachers    

年代:1955

数据来源: AIP

摘要:

The basic principles of an electrostatic strong-focusing lens are described in order to illustrate a modern application of several classical concepts. The motion of an ion in the electrostatic field is described in terms of optical analogies to thick lenses. The astigmatism of such lenses is discussed, and the two-section lens designed for use with the Naval Research Laboratory 5-Mev Van de Graaff proton beam is described.

ISSN:0002-9505    

DOI:10.1119/1.1933974

出版商:American Association of Physics Teachers    

年代:1955

数据来源: AIP

摘要:

The theory of deformation in matter which has been constructed by Eyring, his co-workers, and former pupils as an adaptation of the chemical reaction-rate theory is, in the present article, reviewed on the basis of concepts falling in the domain of physics in the more restricted sense. The theory of the physical phenomena of deformation, elasticity and flow is developed directly from statistico-mechanical fundamentals, without the introduction of concepts of chemical kinetics. Application of the basic theory to deformation in crystalline solids, as well as polymeric materials, is treated in some detail, and finally the work of numerous investigators who have contributed to the theory is briefly recounted.

ISSN:0002-9505    

DOI:10.1119/1.1933975

出版商:American Association of Physics Teachers    

年代:1955

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1933976

出版商:American Association of Physics Teachers    

年代:1955

数据来源: AIP

摘要:

There seems to be some difficulty in understanding the basic principles underlying the working of the Stillson type of wrench, and the object of the present article is to elucidate these from considerations of elementary statics. It is found that such considerations suffice to give an explanation of the way in which the wrench works, and an attempt is made to give a measure of the efficiency of the wrench by deriving the “torque magnification factor.”

ISSN:0002-9505    

DOI:10.1119/1.1933977

出版商:American Association of Physics Teachers    

年代:1955

数据来源: AIP

摘要:

A simple experiment is described for demonstrating the whip effect in a falling chain. The observed reduction in fall time due to the concentration of energy in the falling section of the chain agrees well with the assumption of small energy loss in the loop of the chain. The measured tension at the support point rises far above the maximum value which would be reached in the absence of energy concentration.

ISSN:0002-9505    

DOI:10.1119/1.1933978

出版商:American Association of Physics Teachers    

年代:1955

数据来源: AIP