PH 122 Lecture Notes - Electrostatics
Document Summary
Gravity, the force that we are most familiar with, is pretty wimpy compared to the forces of electrostatics. But whereas there is only one type of gravitational charge (mass) and so all objects attract one another gravitationally, there are two signs of charge: + and. And, as ben franklin discovered, like charges repel and opposites attract. This means that neutral matter with as many + charges as - will not be attracted or repelled from other neutral matter. Thus, the force that matters most on a daily basis is in fact gravity. (there is one proviso here. Where matter comes into contact with other matter, the electrostatic forces do come into play!) When two surfaces make contact, electrons may move from one surface to the other, creating an excess of electrons on one surface (a negative surface), and a lack of electrons on the other (a positive surface). This process does not create charge, it merely separates charges.
