Electric Charges and Forces

Electric Charges and Forces

1. Electric Charge

   • Rubbing objects together can charge them
   • Electric charge comes in two distinct types
     • Positive and Negative Charge
   • Atoms have positive, negative and neutral particles
     • Electrons
     • Protons
     • neutrons
   • Electric charge is quantized
   • A Coulomb is a large amount of charge
   • Electric charge can be transferred between objects
   • Charging by contact varies with material
     • Turboelectric Charging
     • Charging by Collision
   • An electric charge can attract a neutral object
     • The Polarization Process
   • Not all materials are good conductors
     • Free Electrons

2. Electric Force

   • Coulomb's Laws describes the electric force
   • Electric force acts along a line between the charges
   • Electric force is similar to gravitational force
     • Similarities and Differences
     • Astronomical System
     • Atomic Systems
   • Electric forces keep most objects close to neutral

3. Combining Electric Forces

   • Electric forces add by vector addition
   • Electric forces can be added graphically
   • A spherical distribution of charge acts just like a point change
     • surface Charge Density