File:Electric Forces and Fields chapter 18 review.doc

Electric charge is the fundamental quantity that underlies all electrical phenomena. There are two types of charges, positive and negative, and like charges repel each other, and unlike charges attract each other. A conductor is a material through which charge can easily flow due to a large number of free electrons, whereas an insulator does not allow charge to flow freely through it. The force between charges can be found by applying Coulomb’s law. The electric field around a charge is the force per unit charge exerted on another charge in its vicinity.