ELECTRICITY One of electricity’s brightest ideas the lightbulb has long represented the initial spark of human thought and creativity www istock photo com Bart Coenders This book offers a concise view of electricit its history and how it works Readers will discover just what causes the
INTRODUCTION sometimes hair raising power of static elec tricity as well as how electric fields work These pages also explore and explain what happens when electricity flows the relation ship between electricity and magnetism how motors and generators fit into the elec tromagnetic landscape and how centuries of discoveries both accidental and inten tional have changed our understanding of and ability to control electricity It is worth noting and is probably no accident that the visual metaphor for that most central of all human creations the idea is expressed by a lightbulb Although electricity is a form of power that has transformed everyday life it none theless often takes a power outage for us to consider just how important electricity is to everything that we do This book shows just what is behind the awesome power of those impossibly tiny particles the electron and the protonſ and how their movement is essential to life itself
CHAPTER 1 THE FUNDAMENTALS OF ELECTRICITY lectricity is a form of energy associ ated with the atomic particles called electrons and protons In particular electricity involves the movement or accu mulation of negatively charged electrons in relation to positively charged protons The world's modern economies with their industrial transportation and com munication systems were made possible by electricity Old energy forms such as water and steam imposed limitations on production limitations on where goods could be produced and on how much could be produced Electricity has few such lim its it can go anywhere even far into space The development of electricity has resulted in the total transformation of civili zation It brings power into homes to operate lights kitchen appliances television sets radios furnaces computers garage
THE FUNDAMENTALS OF ELECTRICITY and more So common are its uses that one cannot imagine today s world without it Streets would not be lit Telephones would not work Storefronts and factories would be dimmed Electrical forces are also responsible for holding body cells together in the shape they have In fact electrical forces are fun damental in holding all matter together As printed words are being read electric cur rents speed along nerve cells from eye to brain The effect of an electric current can be seen in the flash of lightning between thundercloud and Earth as well as in the spark that can be produced when one walks on a carpet in a dry room STATIC ELECTRICITY AND ELECTRIC CHARGE Understanding electricity begins with describing its effects One way to begin is to examine interactions that occur when electricity is at rest in a form called static electricity Static electricity can be seen at work when hair is combed on a cold dry day As the comb is pulled through strands of hair stand out stiffly Some kind of force II
