Electric Charge Electric charge is a property of tiny particles in atoms. The unit of electric charge is the coulomb (C). A quantity of charge should always be identified with a positive or a negative sign. Figure 5.4.1: The electrostatic force →F between point charges q1 and q2 separated by a distance r is given by Coulomb’s law. Note that Newton’s third law (every force exerted creates an equal and opposite force) applies as usual—the force on q1 is equal in magnitude and opposite in direction to the force it exerts on q2.
Chapter 19 Electric Charges, Forces, and Fields 19.1 Electric Charges 19.2 Insulators and Conductors 19.3 Coulomb’s Law 19.4 The Electric Field 19.5 Electric Field Lines 19.6 Shielding and Charging by Induction