Physics is the most fundamental of the sciences, and some knowledge of it is required in fields as disparate as chemistry, biology, engineering, medicine, and architecture. Our experience in teaching physics to a wide variety of audiences in the U.S. and Europe over many years is that, while students may acquire some familiarity with formal concepts of physics, they are all too often uneasy about applying these concepts in a variety of practical situations. As an elementary example, they may be able to quote the law of conservation of angular momentum in the absence of external torques, but be quite unable to explain why a spinning top does not fall over. The physicist Richard Feynman coined the phrase “fragile knowledge” to describe this kind of mismatch between knowledge of an idea and the ability to apply it.

In our view there is really only one way of acquiring a robust ability to use physics: the repeated employment of physical concepts in a wide variety of applications. Only then can students appreciate the strength of these ideas and feel confident in using them. This book aims to meet this need by providing a large number of problems for individual study. We think it very important to provide a full solution for each one, so that students can check their progress or discover where they have gone wrong. We hope that users of this book will be able to acquire a working knowledge of those parts of physics they need for their science.