摘要:

The question of whether it is possible to design a kettle in which water could be brought to a boil silently is addressed. In this context, acoustic phenomena associated with the heating of water in various vessels are investigated. It is shown that much of the sound emitted in the boiling process can be attributed to coupling between vapor bubble generation and collapse with the natural acoustic modes of the heating vessel utilized. Differences between the thermoacoustic characteristics of deionized and tap water heating are evaluated.

ISSN:0002-9505    

DOI:10.1119/1.16784

出版商:American Association of Physics Teachers    

年代:1991

数据来源: AIP

摘要:

Main concepts in critical phenomena such as universality, critical dimension, analogies with the statistics of polymers and scaling theory, together with renormalization group ideas and rudimentary methods in field theory are presented through the simple and intuitive properties of random walks. This work, which requires little previous knowledge of mathematics besides elementary calculus, has served as the basis of a program to introduce undergraduate students to research in theoretical physics.

ISSN:0002-9505    

DOI:10.1119/1.16785

出版商:American Association of Physics Teachers    

年代:1991

数据来源: AIP

摘要:

Using the Huygens integral an exact, closed‐form solution is obtained for the axial radiation field of a spherical shell section source. The calculation is appropriate to an introductory, calculus‐based physics course. Applications include ultrasonic inspection transducers and optical diffraction.

ISSN:0002-9505    

DOI:10.1119/1.16786

出版商:American Association of Physics Teachers    

年代:1991

数据来源: AIP

摘要:

This paper proposes and solves two problems in classical mechanics that are tied closely to the geometry of the Platonic solids. The problems are: (1) to calculate the gravitational collapse time of a set of identical point masses released from rest from the vertices of a regular polyhedron; and (2) to calculate the moment of inertia (about any axis through the center) of a uniform body in the shape of one of the Platonic solids. Dimensionless figures of merit are introduced to gauge the relative performance of the Platonic solids in each of the problems studied. These figures of merit are similar to the isoperimetric quotient introduced by George Polya a long time ago. The rhombic dodecahedron and triacontahedron are also considered, and it is shown that the triacontahedron surpasses the performance of the Platonic solids in two of the problems examined.

ISSN:0002-9505    

DOI:10.1119/1.16787

出版商:American Association of Physics Teachers    

年代:1991

数据来源: AIP

摘要:

The motion of charged particles in magnetic fields whose magnitude varies as a power of one of the coordinates in the plane of the motion is investigated. For interesting power laws, the parametric equations for the trajectory are expressible in terms of Jacobi elliptic functions. These represent a rather natural generalization of the elementary trigonometric solutions that are encountered in the case of a constant magnetic field.

ISSN:0002-9505    

DOI:10.1119/1.16788

出版商:American Association of Physics Teachers    

年代:1991

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.16789

出版商:American Association of Physics Teachers    

年代:1991

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.16790

出版商:American Association of Physics Teachers    

年代:1991

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.16791

出版商:American Association of Physics Teachers    

年代:1991

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.16792

出版商:American Association of Physics Teachers    

年代:1991

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.16793

出版商:American Association of Physics Teachers    

年代:1991

数据来源: AIP