7.3 - Electric Fields

• What symbol represents the permittivity of free space?

  
• When calculating force between two particles, what can air be treated as?

  A vacuum
• For a charged sphere, the charge can be assumed to to be at what part of the sphere?


  The centre
• Which is stronger? The gravitational force of subatomic particles or the electrostatic force?

  The electrostatic force
• What is electric field strength?

  The force per unit charge acting at a point in an electric field
• What is the magnitude of E (electric field strength) in a uniform electric field?

  Potential difference between plates (V)/Distance between plates
• What is the trajectory of a particle entering a uniform field at right angles?

  It is parabolic
• How is electric potential related to electric field strength?

  E = V / R