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 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
• How do you measure the angle of incidence?

  Measure 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?

  Surface is smooth and flat
• Why can you see your reflection in a mirror?

  Because of specular reflection from a smooth surface
• What happens with light rays on a rough surface?

  They are reflected in different directions
• What is diffuse reflection?

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

  Because of diffuse reflection from a rough surface
• What is true about the angle of incidence in both types of reflection?

  It is always equal to the angle of reflection
• How do normals behave on a rough surface?

  They point in different directions
• What is the significance of the normal in ray diagrams?

  It helps measure angles of incidence and reflection