The purpose of this lab is for you to gain further understanding of refraction.

Towards that end, please work with your colleagues to design a lab using refraction.

Some examples that came up in our brainstorming last week are:

  • Is the speed of light different in coke and diet coke?
  • Does the speed of light change between various types of soda pop?
  • In what beverage is the speed of light the slowest?

To do these (and related) investigations, you'll need to measure the angle of incidence and the angle of refraction.

You can do this using our pencil method (if you recollect that the angles are measured somewhat differently than we might expect) or use a laser pointer.

The math that you need to assist you is:

NOTE that the subscript 1 is the incident angle and the subscript 2 is the angle of refraction

  • Snell's Law (sometimes called 'The law of refraction'):

n1sin Θ1 = n2sinΘ2

  • The ratio of the velocity of light in air to the velocity of light in another tranluscent medium is equal to the INVERSE of the ratio of the index of refraction in air to the index of refraction of that second medium:

v1/v2 = n2/n1

  • The ratio of the sine of the angle of refraction to the sine of the angle of incidence is equal to the ratio of the speed of light in the second medium to the speed of light in air

sin Θ2/sinΘ1 = v2/v1