Introduction Investigations in and out of the laboratory have been at the forefront of physics discoveries for most of the last two centuries. The Cavendish Laboratory, at Cambridge University in England, has seen some of the most remarkable and pioneering discoveries since it was established in the 19th century. J.J. Thomson discovered the electron and Ernest Rutherford was able to recreate fission. Their experimental methods and consequent discoveries revolutionised physicists’ views on the world. Without the art of experimentation, none of these discoveries would have been possible. Practical skills form the backbone of any physics course. It is hoped that, by using this book, you will gain confidence in this exciting and essential area of study. This book has been written to prepare Cambridge IGCSE physics students for both the practical paper and the alternative to practical paper. For either paper, you need to be able to demonstrate a wide range of practical skills. Through the various investigations and accompanying questions you can build and refine your abilities so that you gain enthusiasm in tackling laboratory work. Aside from the necessary exam preparation, these interesting and enjoyable investigations are intended to kindle a passion for practical physics. Great care has been taken to ensure that this book contains work that is safe and accessible for you to complete. Before attempting any of these activities, though, make sure that you have read the safety section and are following the safety regulations of the place where you study. Where practical investigations and or/related questions in this Practical Workbook contain extended syllabus material, this has been identified by a thin vertical bar in the margin next to the relevant material. Gradient calculations in all topics are extension material and are used in this Workbook to allow students to gain confidence in their graphical skills, and to become comfortable with visualising relationships between variables.
Introduction
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