Req Practical 9: Reflection and Refraction

• What equipment is used in the investigation of reflection and refraction?

  • Ray box
  • Lens
  • Slit
• What safety precaution should be taken with the ray box?

  Switch it off when not in use
• Why is a ray box considered safer than a laser?

  Lasers can be more dangerous
• What is the first step in the practical investigation?

  Draw a straight line on A3 paper
• What do you label the line drawn at right angles?

  Normal
• Where should the glass block be placed in relation to the normal?

  Near the center of the block
• What should you do after placing the glass block?

  Turn off the lights in the room
• What is the incident ray?

  The ray hitting the block at the normal
• What is the angle of incidence?

  Angle between incident ray and normal
• What happens when the angle of incidence changes?

  The angle of reflection remains the same
• What do you mark to show the path of the rays?

  Crosses
• What do you measure with a protractor after the experiment?

  Angles of incidence, reflection, and refraction
• How do the angles of incidence and reflection compare for glass and perspex?

  They are the same for both materials
• Why does the angle of refraction differ between materials?

  It depends on the material's properties
• What should you expect when using different materials like glass and perspex?

  • Angles of incidence and reflection are the same
  • Angle of refraction differs between materials
• What is the overall process of the practical investigation?

  1. Draw a straight line and normal
  2. Place glass block and turn off lights
  3. Direct ray of light at normal
  4. Mark incident, reflected, and transmitted rays
  5. Measure angles with protractor
  6. Repeat with different materials