GenPhy

• Electric Charge

  Objects become electrically charged either by gaining or losing electrons.
• Electric Charge


  Every object acquires this ability to attract small pieces of matter after being rubbed against another object.
• Electrostatics - study all phenomena associated with electric charges at rest.
• Amber: Translucent yellowish resin rubbed with a piece of cloth attracts nearby objects.
• Queen Elizabeth I of England found out that many other substances possess the same ability as that of amber when rubbed against other substances.
• Conductors and Insulators

  Conductivity is the measure of the ease at which an electric charge moves through a material.
• Conductors


  Materials that allow the flow of charges through them.
• Conductors


  Have plenty of free electrons that can easily move in the materials.
• Semiconductors


  Intermediate between conductors and insulators.
• Semiconductors


  Conductivity is low in its pure form.
• Insulators


  Materials that resist the flow of charges.
• Doping


  Refers to atoms of different elements in very small amounts added to pure semiconductors to improve conductivity.
• Superconductors


  No resistance to the flow of charges below some critical temperatures.
• Superconductors


  Only works at temperatures close to absolute zero
• Superconductors


  The highest known critical temperature of a superconducting material is 203 K (-70 degrees C) hydrogen sulfide
• Early Greeks

  She called these substance electrics and this ability of amber electricity.
• Electric charge represented as = q
• Unit for charge is coulomb = C