CHAPTER TWO An introduction to electric charge Any Electricity may be described as the phenomenon of electric charge in motion. study of electricity, and the closely related phenomenon of magnetism, is necessarily concerned with the study of the behaviour of electric charges. To better appreciate and understand even the simplest of electric circuits it is first necessary to discuss what is meant by 'electric charge'. In this chapter we introduce electric charge as something which explains the results of some simple experiments. We will be interested in how charges interact with each other, i.e. in the forces that exist between them. One of our main conclusions will be that electric charges interact with each other under the influence of electric forces. Having discussed the effects of electric charge, it is then convenient to discuss the source of electric charge. We will find that all of matter is made up of simple components called atoms, which are made up of equal amounts of positive and negative charge. 2.1 Electric charge

Fig: 1