To Heidi Christopher Alexa and Carson you complete me J R
CONTENTS INTRODUCTION 5 CHAPTER ONE CIRCUITS GET ELECTRICITY MOVING 6 CHAPTER TWO DEVICES IN A CIRCUIT 15 CHAPTER THREE PARALLEL AND SERIES CIRCUITS 19 CHAPTER FOUR WHEN CIRCUITS STOP CIRCULATING 25 CHAPTER FIVE AC AND DC 30 EXPERIMENT MAKE YOUR OWN CIRCUIT 34 Solve It Answer Key 35 Glossary 36 Selected Bibliography 37 Further Information 38 Index 39
NASA astronauts Scott Kelly top and Terry Virts bottom are working in the Destiny Laboratory of the International Space Station ISS The circuits that provide power to the ISS allow astronauts to live and work in space
INTRODUCTION A lightning storm is crackling outside when suddenly the lights go out Out the window you see that other homes on your street are also without power Eventually the lights come back on You find out later that a bolt of lightning struck some of the equipment that supplies electricity to your neighborhood To restore the electricity the power company had to repair the large electrical circuit that provides energy to the homes on your street and others nearby A circuit is a path that electric current travels to provide energy to lights cities or anything that needs electricity to work A circuit is a closed path it begins and ends in the same place without a break anywhere along the way During the lightning storm that closed path opened up the electric current was stopped at least for a little while Circuits are at the heart of all electronics Without them we wouldn’t be able to power computers speakers the electric lights in your home or even the International Space Station To really understand how electricity is used all around you you need to know your circuits 5
