physics electricity

• Electric Charge


  • A physical property of an object that causes to be attracted toward or repelled from another charged object
  • Divided into two types: positive and negative
• Charging Mechanisms


  1. Charging by Friction

  2. Charging by Conduction

  3. Charging by Induction
• Charging by Friction


  • A neutral body can gain charge by rubbing or friction
  • Nuclei of the objects' atoms pull their electrons with different strengths
• Triboelectric Series


  • A list of materials arranged in increasing electron affinity
  • Electron Affinity - measure of an atom's attraction to an electron
• Charging by Conduction


  Requires physical contact between a charging body and a neutral body
• Charging by Induction


  Requires no physical contact between a charging body and a neutral body
• Insulators vs Conductors

  • Insulators - Materials that resist the flow of charges (e.g. rubber, glass, oil, diamond, dry wood, pure distilled water)
  • Conductors - Materials that readily allow the flow of charges through them (e.g. Silver, Gold, Copper, Steel, Sea Water)
• Conductivity


  The measure of ease at which an electric charge moves through a material
• Semiconductors


  They are not as conductive as metals but they are more conductive than insulators like rubbers (e.g. Silicon)
• Superconductors


  Offer practically no resistance to the flow of charges (e.g. Mercury)
• Coulomb's Law Equation


  The mathematical formula to calculate the electrostatic force vector between two charged particles
• Charge can only flow through conductors like metals.