Physics in the Modern World

Book Preface

This is a text for a one-year introductory course in physics for students who are specializing in other disciplines. In these chapters you will find a survey of topics in physics with emphasis on those aspects that are of current interest. No mathematics beyond basic trigonometry is required to follow the discussions.

Today we live in a world that is dominated by technology. More ver, the impact of technology on society, already enormous, will almost certainly continue to increase. In order to cope with the problems of a highly technical world, it is necessary to appreciate some of the basic scientific ideas that are the foundation stones upon which our modern technology is built. Lacking this understanding, we would find it increasingly difficult to contribute effectively to the complex decisions that affect our everyday lives. It is the purpose of this book to put forward these fundamental ideas as clearly as possible and to draw attention to the way that basic physical principles are applied in our technological world. In Physics in the Modem World you will see that physical principles bring a pattern of simplicity and continuity to the diverse natural and technological world  around us. To show the many ways in which physical ideas are manifest in everyday situations, numerous short essays on various kinds of applications have been included.

In these special sections you will learn about the operation of rockets and cameras, and about the principles at work in space travel and X-ray photography. Discussions of automobile air bags, drag racing, artificial gravity, pollution control, appliance economics, musical instruments, radar, and other modern phenomena and devices emphasize the way that physical principles are applied in today’s world. Historical sketches of individual scientists detail their important contributions to our present knowledge and technology. Physics is not an abstract subject. Physical principles form the basis of the world in which we live, and they constitute a vital part of the knowledge we must have to understand and appreciate that world.

An important part of learning about physics is becoming familiar with some of the quantitative aspects of the subject by solving simple problems. Each chapter concludes with a list of exercises—some questions and some numerical problems. You should answer as many of these as possible to test and reinforce your comprehension of the text material. (Answers to the odd-numbered numerical exercises are at the back of the book. The more difficult problems are marked with an asterisk, *.)

A serious effort has been made to present each topic in the clearest possible terms. The explanations are developed carefully and in depth, frequently including a detailed example. Accordingly, this book is more than a source of questions for the instructor to answer. It is a book that you, the student, can read.

In this second edition some of the material has been reorganized along more traditional lines, and several new topics have been introduced. A number of worked examples considerably expanded. The text has been carefully scrutinized and many of the explanations have been clarified and improved.

To enhance the value of this text as a learning tool, a supplementary student guide is available. In this guide the student will find a short summary of the important ideas in each chapter, some additional worked examples, suggestions for outside reading, and a list of questions and problems (with answers) to test your comprehension of the material. I hope that you, the reader, will enjoy this book as much as I have enjoyed writing it!

JERRY B. MARION
College Park, Maryland