Questions for Refraction Lab

This lab will investigate four aspects of reraction.
  1. How light is is refracted from a less dense medium (air) into a more dense medium (Lucite) (Part I)
  2. How light is refracted from a more dense medium to a less dense medium
  3. Snell's Law and the Laws of Refraction
  4. The index of refraction or optical density of a particular medium

This lab was done in two parts based on

  1. Light travelling from a less dense medium (air) into a more dense medium (lucite)
    Angles of incidence and refraction are measured and their corresponding sine values are recorded. The ratio of sin i to sin R is calculated and sin i versus sin R is plotted and the slope is determined.
  2. The above is repeated for light travelling from a more dense medium into a less dense medium.

Questions for Part I

  1. When light travels down or along a normal what happens to it?
  2. When light is refracted on pass from a less dense medium to a more dense medium it always bends____________________ .
  3. The incident and refracted rays are located on the _______________ sides of the normal.
  4. How does the angle of incidence compare to the angle of refraction?
  5. Graph sin i versus sin R and calculate the slope of this line. Make a comment about its value.
  6. The ratio of sin i to sin R should be a ____________. Your reported average value is ________ .
  7. Why wasn't your ratio the same in each case? This is the experimental error in the experiment.
    Give reasons for the error.
  8. State Snell's Law.
  9. What is this ratio called, and what should your value have been? Research is required.
  10. An incident ray travels from air into water at an angle of 34.6o. Determine the angle of refraction.

Part 2

  1. When light is refracted on pass from a more dense medium to a less dense medium it always bends____________________ .
  2. How does the angle of incidence compare to the angle of refraction?
  3. At what angles did reflection occur?
  4. Note: The Laws of Refraction cannot and do not apply to reflection.
  5. What is the average of your ratios (sin i to sin r). How did this value compare to the value obtained in Part I?
  6. How does the angle of incidence compare to the angle of reflection? Assume experimental error, what should have occured?
  7. Define the term Critical Angle.
  8. What happens to all of the light once the angle of refraction has reached its maximum or critical value?
  9. How would you experimentally determine the critical angle of a substance?
  10. From your experiment, the refractive index for light travelling from air to lucite is ___________, and from lucite to air the refractive index is __________. How are these two values related?
  11. Calculate the index of refraction for crown glass. (Show all steps and use table 10.1 page 366)