AP Physics 2 Lab – Index of Refraction

The goal is to determine an experimental value for the index of refraction of water and to verify Snell’s Law.

Record of the Experiment:

1. Create a well-labeled diagram showing how the angles were measured.

Method 1:  Statistical and Algebraic Analysis

1. Make a table with five columns – one each for the angles θ₁ and θ₂, two more columns of calculated values that can be used to produce a linear graph of the angle data, and a column of the index of refraction, calculated using the angles of each trial.  (Hint:  consider Snell’s Law in order to determine what plotted values would yield a linear graph – this will determine what to calculate for the third and fourth columns of the table.)
2. Determine the mean value and percent deviation in the column of index values.
3. Determine the percent error in the mean value given the accepted value n = 1.33.

Method 2:  Graphical Analysis – Linearization of Data

1. Produce a large, high quality, scientific graph of the third and fourth column of the table.  Determine the line of best fit, including equation and correlation coefficient, shown on the graph.

2. Using the coefficient(s) from the equation of the line, determine the index of refraction.  Show your work and/or explain!

Completed report:

· Well-labeled diagram showing the lab setup and the angles θ₁ and θ₂.

· Table with data and calculated values – 5 columns and at least 5 trials (rows)

· Statistical analysis:  mean value, percent deviation, and percent error of index of refraction

· Linearized graph based on angle data with a slope related to the index of refraction

· Graphical analysis:  index of refraction found using slope of best fit and percent error

· Discussion of error – signs thereof and most likely sources.