Refraction practical

• • A raybox. - A rectangular Perspex block and glass block. - White paper. - A sharp pencil, ruler and protractor.
• Step 1: Place a Perspex block on a sheet of paper and carefully draw around it. Step 2: Use a protractor to draw a normal. Step 3: Use the raybox to shine a ray of light into the block at an angle. Step 4: Mark two or three points with crosses along the light rays entering and leaving the block.
• Step 5: Remove the block and raybox and use a ruler to join up the crosses with straight lines. Step 6: Connect the rays on either side of the block to show the path of the light inside the block.
• Step 7: Use a protractor to measure the angle between the incoming ray and the normal (angle of incidence), and the ray inside the block and the normal (angle of refraction). Repeat the experiment with a glass block.
• Why is the angle of refraction smaller than the angle of incidence.

  
  

  This is because glass and Perspex are both more dense than air so light slows down and bends towards