Refraction

• Refraction occurs because waves travel faster in some materials than others
• Wavefronts are closer together in the more optically dense materials showing the decrease in wavelength
• If a wave slows down at a boundary, it bends towards the normal

  If a wave speeds up at a boundary, it bends away from the normal
• Place a transparent rectangular block on a piece of paper

  Trace around it using a sharp pencil

  Keep the rectangular block in the same position

  Use a ray box to shine a ray of light at the middle of one side of the block

  Trace the incident ray on the paper

  Draw the normal line where the light ray entered the block

  Use a protractor to measure the angle of incidence and the angle of refraction