Reflection

• What are the two types of reflection discussed?

  Specular and diffuse reflection
• What happens when a wave arrives at a boundary?

  It can be absorbed, transmitted, or reflected
• What occurs when a wave is absorbed by a material?

  Energy is transferred to the material's stores
• What does it mean for a wave to be transmitted?

  The wave enters the material and continues traveling
• What leads to refraction when a wave is transmitted?

  The wave passes out the other side of the material
• What is the rule for the angles of incidence and reflection?

  Angle of incidence equals angle of reflection
• How do you start drawing a ray diagram?

  Begin with the boundary between two materials
• What does the normal line represent in a ray diagram?

  A dashed line perpendicular to the surface
• How do you measure the angle of incidence?

  Measure the angle between the incoming ray and the normal
• What is the point where the incoming ray touches the boundary called?

  Point of incidence
• What characterizes specular reflection?

  All incoming rays are reflected in the same direction
• Why can't you see your reflection in paper?

  Paper has a rough surface causing diffuse reflection
• How does the surface of a rough material affect reflection?

  Normals point in different directions, scattering light
• What is the relationship between angle of incidence and angle of reflection?

  They are always equal
• What happens to reflected rays from a rough surface?

  They get scattered in different directions
• What are the types of reflection and their characteristics?

  • Specular Reflection:
  • Smooth surface
  • Rays reflected in the same direction
  • Clear image (like a mirror)

  
  

  • Diffuse Reflection:
  • Rough surface
  • Rays reflected in different directions
  • No clear image (like paper)
• What are the steps to draw a ray diagram for reflection?

  1. Draw the boundary between materials.
  2. Draw the incoming ray towards the boundary.
  3. Draw the normal line perpendicular to the surface.
  4. Measure the angle of incidence.
  5. Draw the reflected ray at the same angle as incidence.
  6. Mark the point of incidence.