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## Description

This book is dedicated to basic physical principles of the propagation of
acoustic and elastic waves. It consists of two volumes. The first volume
includes 8 chapters and extended Appendices explaining mathematical aspects
of discussed problems. The first chapter is devoted to Newton's laws, which,
along with Hooke's law, govern the behavior of acoustic and elastic waves.
Basic concepts of mechanics are used in deriving equations which describe
wave phenomena. The second and third chapters deal with free and forced
vibrations as well as wave propagation in one dimension along the system of
elementary masses and springs which emulates the simplest elastic medium.
In addition, shear waves propagation along a finite and infinite
string are discussed.

In chapter 4 the system of equations describing compressional waves is derived. The concepts of the density of the energy carried by waves, the energy flux, and the Poynting vector are introduced. Chapter 5 is dedicated to propagation of spherical, cylindrical, and plane waves in homogeneous media, both in time and frequency domains. Chapter 6 deals with interference and diffraction. The treatment is based on Helmholtz and Kirchhoff formulae. The detailed discussion of Fresnel's and Huygens's principles is presented. In Chapter 7 the effects of interference of waves with close wave numbers and frequencies are considered. Concepts such as the wave group, the group velocity, and the stationary phase important for understanding propagation of dispersive waves are introduced. The final chapter of the first volume is devoted to the principles of geometrical acoustics in inhomogeneous media.

In chapter 4 the system of equations describing compressional waves is derived. The concepts of the density of the energy carried by waves, the energy flux, and the Poynting vector are introduced. Chapter 5 is dedicated to propagation of spherical, cylindrical, and plane waves in homogeneous media, both in time and frequency domains. Chapter 6 deals with interference and diffraction. The treatment is based on Helmholtz and Kirchhoff formulae. The detailed discussion of Fresnel's and Huygens's principles is presented. In Chapter 7 the effects of interference of waves with close wave numbers and frequencies are considered. Concepts such as the wave group, the group velocity, and the stationary phase important for understanding propagation of dispersive waves are introduced. The final chapter of the first volume is devoted to the principles of geometrical acoustics in inhomogeneous media.

## Table of Contents

**Introduction. List of Symbols. Newton's laws and parlide motion.**Newton's laws. Motion of system of particles.

**Free and forced vibrations.**Hooke's law of springs. Free vibrations of the system: mass-spring. Forced vibrations of the system: mass-spring. Principles of measuring vibrations.

**Propagation.**Propagation of waves along a system of masses and springs. Solution of 1-D wave equation. Boundar conditions. Transversal waves in a spring.

**Basic equations for dilatational waves.**Introduction. Wave phenomena in gas and fluid. Wave equation and boundary conditions for dilatational waves. The kinetic and potential energy of the wave flux of the energy Poynting vector. Boundary value problem. Theorem of uniqueness. Gravitational waves in a fluid.

**Waves in homogeneous medium.**Spherical waves from an elementary source. Cylindrical waves from linear source in homogenous medium. Plane waves in homogeneous medium.

**Interference and diffration.**Superposition of waves in an uniform medium, caused by a system of primary sources. Helmholtz formula. Kirchhoff diffration theory. Fraunhofer and Fresnel diffration. Helmholtz - Kirchhoff formula. Huygens - Fresnel principles. Relationship of potential with initial conditions. Poisson's formula. Transition and transportation equations.

**Superposition of sinusoidal waves with different frequencies and wave lengths.**Wave group: Phase and group velocities. Superposition of sinussoidal waves and the method of stationary phase.

**Principles of geometrical acoustics.**Introduction. Rays and their general features. Behaviour of rays when velocity is a function of one cartesian coordinate. Behaviour of rays when velocity is a function of one coordintae

*r*. Rays near interfaces. Time fields.

**Appendices.**Vector algebra. Scalar field and gradient. Vector fields. Complex numbers. Linear ordinar

## Details

- No. of pages:
- 528

- Language:
- English

- Copyright:
- © 2000

- Published:
- 2nd March 2000

- Imprint:
- Elsevier Science

- eBook ISBN:
- 9780080929309

- Print ISBN:
- 9780444503367

## About the authors

### Avital Kaufman

#### Affiliations and Expertise

Department of Geophysics, Colorado School of Mines, Golden, CO, USA

### A.L. Levshin

#### Affiliations and Expertise

Department of Physics, University of Colorado, Boulder, CO 80390, USA

## Reviews

@from:P.G. Malischewsky, Friedrich-Schiller University Jena, Germany
@qu:...the authors have done a good job in presenting wave theory starting with very elementary matters and extending this to the detailed 'ramifications' of waves. This book should be profitably read by students and also by specialists, who do not always have the 'ramifications' at their disposal. I await volume 2 with anticipation.
@source:Geophysical Journal International
@from:J. Zahradnik and O. Novotny, Charles University
@qu:...The book should be extremely valuable for all who need a rigorous physical and mathematical wave-propagation background which, as a rule, is omitted or drastically shortened (thus difficult to understand) in more specialized monographs. Moreover, most explanations include some innovative ideas, interesting analogies, and/or examples that make the text attractive for wave propagation specialists and experienced lecturers, too.
@source:The Leading Edge
@from:H. Kirchner
@qu:...should be useful to graduate students and researchers.
@source:Pure and Applied Geophysics