摘要:

A group of ten fixed-frequency audio oscillators having frequencies related by110(N), whereNis an integer, are used. Details of construction of oscillators, audio amplifier, and associated power supply are given. With the oscillators it is possible to demonstrate production of synthetic first and second harmonics by playing two or more tones simultaneously. Five characteristic tones may be played simultaneously to simulate a bell-like tone.

ISSN:0002-9505    

DOI:10.1119/1.1933040

出版商:American Association of Physics Teachers    

年代:1951

数据来源: AIP

摘要:

The paper describes experiments on thin films that can be done easily with Boys' rainbow cup, mounted on a phonic wheel to insure constancy of rotational speed. Although the air within the cup, on one side of the film, has free access to the atmosphere on the other side of the film, the film itself is spherical. A quantitative explanation of the effect is given in terms of Bernoulli's principle.

ISSN:0002-9505    

DOI:10.1119/1.1933041

出版商:American Association of Physics Teachers    

年代:1951

数据来源: AIP

摘要:

Though it is frequently stated that binary numeration was first formally proposed by Leibniz as an illustration of his dualistic philosophy, the mathematical papers of Thomas Hariot (1560–1621) show clearly that Hariot not only experimented with number systems, but also understood clearly the theory and practice of binary numeration nearly a century before Leibniz's time.

ISSN:0002-9505    

DOI:10.1119/1.1933042

出版商:American Association of Physics Teachers    

年代:1951

数据来源: AIP

摘要:

This paper supplements an earlier discussion of Cartesian ovals. Assuming for the first medium a refractive index 1.00, and for the second 1.50 (and vice versa), the forms of these ovals for refraction have been studied for numerous cases. Each curve represents the form for a specified value ofk, the ratio of image distance to object distance. The values ofkrun from +∞ to −∞.

ISSN:0002-9505    

DOI:10.1119/1.1933044

出版商:American Association of Physics Teachers    

年代:1951

数据来源: AIP

摘要:

This paper deals with the scope of the borderline field between aerodynamics and physics, which has become known as aerophysics. It emphasizes the desirability of utilization of ballistics ranges for aerophysics investigation. In this connection, it reviews in outline form the history of ballistics: the age of speculative ballistics, the age of geometrical ballistics, the age of physical ballistics. Examples of aerophysical research are cited from aeroballistics (high speed gas flows) investigations conducted at the Naval Ordnance Laboratory, White Oak, Maryland.

ISSN:0002-9505    

DOI:10.1119/1.1933045

出版商:American Association of Physics Teachers    

年代:1951

数据来源: AIP

摘要:

Measurements of the radiation in the neighborhood of an unshielded demonstration x-ray tube give intensities ranging from 6 roentgens per minute within a few cm of the tube to no appreciable radiation per minute a few meters from the tube. The genetic and body effects of radiation are discussed. These effects are such that x-ray demonstrations should be given with greater care than is perhaps now generally exercised.

ISSN:0002-9505    

DOI:10.1119/1.1933047

出版商:American Association of Physics Teachers    

年代:1951

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1933048

出版商:American Association of Physics Teachers    

年代:1951

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1933050

出版商:American Association of Physics Teachers    

年代:1951

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1933054

出版商:American Association of Physics Teachers    

年代:1951

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1933056

出版商:American Association of Physics Teachers    

年代:1951

数据来源: AIP