PHYSICS 3.1

• Charge (C)

  A fundamental attribute of matter particles which determine their behavior within an electromagnetic field
• Charge is denoted by q and is measured in coulomb (C)
• Mass and charge of selected subatomic particles

  • neutron (n): 0, 1.6749 x 10^-27 kg
  • proton (p): +1.602 x 10^-19 C, 1.6726 x 10^-27 kg
  • electron (e): -1.602 x 10^-19 C, 9.1094 x 10^-31 kg
• Unlike charges attract, like charges repel
• Polarization is a concept in electricity
• Types of Materials according to conductivity

  • Conductors
  • Insulators
  • Semiconductors
  • Superconductors
• Electric Current

  The net flow of electrons through an object
• The sum of electric charges in any closed system is conserved or does not change
• The magnitude of charge of an electron or a proton is a natural unit of charge equivalent to 1.602 x 10^-19 C
• Charging by Friction

  Occurs when two different materials are rubbed together
• Electron affinity

  The property of a material to attract electrons
• Triboelectric series

  • A ranking of some common materials based on their electron affinity
• Charging by Conduction

  The process of charging an uncharged conductor by bringing it in electrical contact with a charged body
• Charging by Induction (negatively charged body) - Polarization

  1. Neutral body needs to be grounded

  2. Electrons will travel up the ground connection if the charging body is positive

  3. Electrons will travel down the ground if the charging body is negative

  
• Safety features in design of buildings, electronic components, and appliances to avoid electrostatic discharges

  • Avoid hand contact by transporting and storing products in static-safe containers
  • Keep electrostatic-sensitive parts in their containers until they arrive at static-protected workstations
  • Place parts in a static-protected area before removing them from their containers