Electrostatics, Electron Beams and Radioactivity

Abstract

There are two sorts of charge, positive and negative. A polythene rod rubbed with wool becomes negatively charged, and a cellulose acetate rod rubbed with wool becomes positively charged. Like charges attract and unlike charges repel. Charge may be detected using a gold leaf electroscope (see Example 14.5). If the leaf of a charged electroscope diverges further when a body is brought up to it, that body is charged. The sign of the charge on the body is the same as that on the electroscope.