electric charges and forces

electric charges and forces

1. electric force

   • coulombs las describes the electric force
   • electric force acts along a line between the charges
   • electric forces keep most objects close to neutral
   • electric force is similar to the gravitational force
     • similarities and differences
     • atomic systems
     • astronomical system

2. electric charge

   • not all materials are good conductors
     • free electrons
   • a coulomb is a large amount of charge
   • electric charge is quantizied
   • electric charge comes in 2 distinct types
     • positive and negative energy
   • rubbing objects together can charge them
   • electric charge can be transferred between objects
   • charging by contact varies with materials
     • charging by collision
     • turboelectric charging
   • an electric charge can attract a neutral object
     • the polarization process
   • atoms have positive, negative and neutral particles
     • proton
     • electron
     • neutron

3. combining electric forces

   • a spherical distribution of charge acts just like a point change
     • surface change density
   • electric forces can be added graphically
   • electric forces add by vector addition