Iona Prep Physics Puzzles

Lab: To Measure the Index of Refraction


The index of refraction is defined as the ratio sin(i)/sin(r) where i is the angle of incidence and r is the angle of refraction. Both angles are measured in degrees.
The apparatus consists of a turntable which is controlled by a servo. You set the angle of incidence and the angle of refraction is measured. The light is provided by a small laser pointer.
The turntable looks like this:

n = sin(i)/sin(r)


Please enter your name here:

Certain angles of incidence are available

Note: After pushing the SUBMIT button, be patient. It will take several seconds for the reply to come back.


Of course a single run will not give perfect results. You should run the experiment several times, put your data into a table, compute the index of refraction for each run and then use the average for your experimental result.

Conclusion: the speed of sound in the unknown gas was found to be .........