Properties and Wave Behavior of Light

• Light


  Electromagnetic wave that can be described as both a wave and a particle
• Properties of light


  • Reflection
  • Refraction
  • Transmission
  • Absorption
  • Dispersion

  
• Reflection


  1. Incident ray

  2. Refracted ray

  3. Normal line

  4. Angle of incidence

  5. Angle of reflection

  
• Law of reflection


  • The angle of incidence, the angle of reflection, and the normal line lie on the same plane
  • The angle of incidence is equal to the angle of reflection

  
• Types of reflection


  • Specular/regular reflection
  • Diffuse/irregular reflection

  
• Particle nature of light

  Light is made up of discrete packets of energy called photons
• Refraction


  Bending of light due to change in speed when passing obliquely between two different media

  
• Index of refraction


  Ratio of speed of light in a vacuum to speed of light in a material

  
• Transmission


  Passing of light through a material without being absorbed
• Absorption


  Light energy is converted into thermal energy when light strikes a material
• Absorption of light


  • White light is composed of red, orange, yellow, green, blue, and violet
  • White object reflects all components of light
  • Black object absorbs all components of light
  • Leaf absorbs all frequencies except green

  
• Dispersion


  Separation of white light into its component colors due to refraction

  
• Wave properties of light

  • Transverse wave
  • Light scattering
  • Diffraction
  • Interference

  
• Light scattering


  Particles absorb light and scatter it in all directions, depends on particle size and wavelength

  
• Rayleigh scattering


  Scattering of light depends on relative size of particles and wavelength

  
• Mie scattering


  Scattering of mostly white light, depends less on wavelength
• Diffraction


  Spreading of light when it encounters an obstacle or opening, depends on size of opening and wavelength

  
• Interference


  Combination of two or more waves into one wave when they pass through the same point
• Types of interference


  • Constructive interference
  • Destructive interference
• Diffraction and interference patterns


  • Distance between lines corresponds to wavelength