Electric Charges The law of electric charges states that like charges repel and opposite charges attract. _ _ _
Strength of the Electrical Force The size of the electric force between two objects depends on the size of the charges exerting the force and the distance between the objects. Smaller force Larger force Larger Force Smaller Force
Charged Objects Charged objects exert a force on each other and can cause each other to move. Objects become charged when they gain or lose electrons. Anion- when an atom gains electrons- negative Cation- when a atom loses electrons- positive Objects may become charged by FRICTION, CONDUCTION, or Polarization.
Three ways of charging an object Friction- when charges are passed from one object to the other by rubbing the objects together. Conduction-when you touch an object with another object that has a charge, the charge is transferred from one object to the other. Polarization- when charges in an uncharged metal object are rearranged without direct contact.
The law of Conservation Charges are not created or destroyed they are said to be conserved. Charges move easily in conductors but do not move easily in insulators. Conductor- a material in which electrons move easily Good Conductors: copper, aluminum, and mercury Insulator- a material in which electrons do not move easily Good Insulators: Plastic, rubber, glass, wood, and air.
Vocabulary Static Electricity- the buildup of electric charges on an object. The charge is lost through electric discharge. Electric Force- the force between charged objects Electric Field- the region around a charged object in which an electric force is exerted on another charged object. Field lines point toward negative charges and away from positive charges.