Reflection and refraction

• What is the angle of incidence equal to?

  Angle of reflection
• How is the angle of incidence defined?

  It's the angle between the incoming wave and the normal.
• What does the angle of reflection represent?

  It's the angle between the reflected wave and the normal.
• What is the normal in the context of reflection?

  An imaginary line perpendicular to the surface.
• How is the normal typically represented in diagrams?

  As a dotted line.
• What is required for total internal reflection to occur?

  The wave must travel from dense to less dense material.
• What happens when a wave hits a surface above the critical angle?

  Total internal reflection occurs.
• What is specular reflection?

  Reflection in a single direction by a smooth surface.
• Give an example of specular reflection.

  Light reflected by a mirror.
• What occurs during diffuse reflection?

  Waves are reflected in all directions by a rough surface.
• Why does diffuse reflection occur?

  Each incident ray has a different angle of incidence.
• What does a rough surface look like when light is reflected?

  It appears matt with no clear reflection.
• What is the relationship between angle of incidence and angle of reflection?

  They are always equal.
• What is the purpose of using a glass block in the refraction experiment?

  To investigate how light is refracted.
• What should you do to measure the angle of incidence in the refraction experiment?

  Use a protractor at the point of incidence.
• What happens to the light ray as it enters the glass block?

  It bends towards the normal.
• Why does the light ray bend away from the normal when leaving the block?

  Because it speeds up as it enters air.
• What type of waves can be refracted?

  All electromagnetic waves.
• What are the steps to investigate refraction using a glass block?

  1. Place a glass block on paper.
  2. Pass a beam of light onto the block.
  3. Draw the incident and emergent rays.
  4. Draw the normal at the point of incidence.
  5. Measure angles of incidence and refraction.
  6. Repeat and calculate averages.
• What does the refraction experiment demonstrate about light behavior?

  • Light bends towards the normal when entering a denser medium.
  • Light bends away from the normal when exiting to a less dense medium.