IGCSE Physics Third Edition aims to provide an up-to-date and comprehensive coverage of the Core and Extended curriculum in Physics specifi ed in the current Cambridge International Examinations IGCSE syllabus. As you read through the book, you will notice four sorts of shaded area in the text. Material highlighted in green is for the Cambridge IGCSE Extended curriculum. Areas highlighted in yellow contain material that is not part of the Cambridge IGCSE syllabus. It is extension work and will not be examined. Areas highlighted in blue contain important facts. Questions are highlighted by a box like this. The book has been completely restructured to align chapters and sections with the order of the IGCSE syllabus. A new chapter on momentum has been included and the checklists at the end of each chapter are all aligned more closely with the syllabus requirements. New questions from recent exam papers are included at the end of the book in the sections entitled Cambridge IGCSE exam questions, Practical test questions and Alternative to practical test questions. These can be used for quick comprehensive revision before exams. The accompanying Revision CD-ROM provides invaluable exam preparation and practice. Interactive tests, organised by syllabus topic, cover both the Core and Extended curriculum.