MEDTERM PHYSICS

• Light


  Electromagnetic radiation with wavelengths between 380 and 750 nm which is visible to the human eye
• Visible light


  Portion of the electromagnetic spectrum that is visible to the human eye, wavelength range (λ): 380 − 750 nm
• Law of reflection


  • The angle of reflection θr is always equal to the angle of incidence θi with respect to the normal
  • The ray of light is traveling in a straight path
  • The reflection is always inverted
• Refraction


  Governed by Snell's law: n1 sin θ1 = n2 sin θ2, where n1 is the index of refraction of material 1, n2 is the index of refraction of material 2, θi is the angle in material 1, and θr is the angle in material 2
• Index of refraction (n)

  Calculated as n=c/v, where c is the speed of light in vacuum (3x10^8 m/s) and v is the speed of light in the medium
• Index of refraction (n)

  If index of refraction is large, the speed of light in that medium is small. If index of refraction is small, the speed of light in that medium is large.
• Total internal reflection


  Complete reflection of a ray of light within a medium back into the medium, occurring if the angle of incidence is greater than the critical angle
• Polarization


  Polarized waves are light waves in which the vibrations only occur in a single plane
• Focal length


  Half of radius: f = r/2, or 1/4 of diameter: f = d/4
• Light


  Electromagnetic radiation with wavelengths between 380 and 750 nm which is visible to the human eye
• Visible light


  Portion of the electromagnetic spectrum that is visible to the human eye, wavelength range (λ): 380 − 750 nm
• Law of reflection


  • The angle of reflection θr is always equal to the angle of incidence θi with respect to the normal
  • The ray of light is traveling in a straight path
  • The reflection is always inverted
• Refraction


  Governed by Snell's law: n1 sin θ1 = n2 sin θ2, where n1 is the index of refraction of material 1, n2 is the index of refraction of material 2, θi is the angle in material 1, and θr is the angle in material 2
• Index of refraction (n)

  Calculated as n=c/v, where c is the speed of light in vacuum (3x10^8 m/s) and v is the speed of light in the medium
• Index of refraction (n)


  If index of refraction is large, the speed of light in that medium is small. If index of refraction is small, the speed of light in that medium is large.
• Total internal reflection


  Complete reflection of a ray of light within a medium back into the medium, occurring if the angle of incidence is greater than the critical angle
• Polarization


  Polarized waves are light waves in which the vibrations only occur in a single plane
• Focal length


  Half of radius: f = r/2, or 1/4 of diameter: f = d/4