Reflection

• What is the focus of today's video?

  Reflection of waves off a boundary
• 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 is the relationship between wavelength and reflection?

  Reflection depends on wavelength and material properties
• What is the rule for drawing ray diagrams regarding angles?

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

  Begin with the boundary between two materials
• In a ray diagram, what does the dashed line represent?

  The normal line perpendicular to the surface
• How do you measure the angle of incidence in a ray diagram?

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

  The point of incidence
• What is specular reflection?

  Reflection from a smooth, flat surface
• Why do mirrors provide clear images?

  They have a smooth surface for specular reflection
• What characterizes diffuse reflection?

  Reflection from a rough surface scattering light
• Why can't you see your reflection in paper?

  Paper has a rough surface causing diffuse reflection
• What happens to normals on a rough surface?

  Normals point in different directions
• What is the significance of the angle of incidence in reflection?

  It is always equal to the angle of reflection
• What are the steps to draw a ray diagram for reflection?

  1. Identify 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.
• What are the differences between specular and diffuse reflection?

  • Specular Reflection:
  • Smooth surface
  • Light reflected in a single direction
  • Produces clear images

  
  

  • Diffuse Reflection:
  • Rough surface
  • Light scattered in multiple directions
  • No clear images visible