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 leads to refraction when a wave is transmitted?

  The wave passes out the other side of the material
• What determines which of the three outcomes occurs when a wave meets a boundary?

  The wavelength of the wave 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
• What does the normal line represent in a ray diagram?

  A dashed line perpendicular to the surface
• What is the point where the incoming ray touches the boundary called?

  The point of incidence
• What characterizes specular reflection?

  All incoming rays are reflected in the same direction
• How does diffuse reflection differ from specular reflection?

  Light is reflected in many directions
• Why can't you see your reflection in paper?

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

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

  They are always equal in both reflection types
• How does the surface texture affect reflection?

  Smooth surfaces cause specular reflection
• What is the main focus of the video?

  How waves reflect off boundaries
• 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. Label the point of incidence.
• What are the characteristics of specular and diffuse reflection?

  • Specular Reflection:
  • Smooth surface
  • Light reflected in one direction
  • Clear image produced

  
  

  • Diffuse Reflection:
  • Rough surface
  • Light reflected in multiple directions
  • No clear image produced