Lab 08 Reexion and Refraction of Light Richard Medina 1. Introduction (Read Ch 24, with particular attention on Ch 24.1-24.4 of the textbook} 2. Procedure A. Reection 1. 2. Open a web browser and navigate to the Bending Light PHET simulation https:// phet.colorado.edu/sims/html/bending-light/latest/bending-light_en.html Select Prisms box option in the simulation with a laser emitting a single ray at 700 nm and check all the boxes on the bottom (Reections, Normal, and Protractor). Select a prism object (triangle in the window) with index of reection of glass and set the environment index of reection as air. Adjust the single ray to strike on one of the plane surface of the prism at an angle of incidence of about 60 with the doted line normal as shown in g. 1 (left side of the prism object). Pay attention only to the incident and reected single ray on that plane surface. Measure the incident and reected angles and calculate the angle difference 9,. a, between the measured values of the incident and reected angles. Record those values in table 1. _ .. H H a m_ [3W do. mu m: gm, Figure 1. Incident and reflecting rays at a plane surface 6. Repeat this process two more times, once for an incident ray of about 45 and once for an incident ray of about 30. Table 1. Reflection of light rays at a plane surface Ray Angle Difference 1 Reflection 2 3 B. Refraction 1 . Keep the prism in the same position as in part A, and adjust the direction of the laser so that the incident ray strikes one face of the prism at an angle of about 60 with the surface normal as shown in fig. 2. Environment Custom Index of Refraction (n) Air Water Glass 650 nm Objects Custom Index of Refraction (n) OR Reflections Normal Water Glass Protractor PhET. = Figure 2. Refraction of a light ray at a plane surface 2. Identify and measure the angles 01, 02, 03, and 04 showed in fig. 3.Figure 3. Determination of the four angles At the rst surface, the index of refraction of the environment is n = 1 (air) and n is the index of refraction of the prism. Then, from Snell's law 1 - sinll1 = n - sin 92 for the rst surface. At the second surface, we obtain n - sin93 = 1 - sin 94 and solving these two equations for It gives sins sins 1 and n = 4 (Eq. 1) sin 62 sin 63 n: Use these two equations to calculate two values of n for each of the incident rays. Take the two values calculated by eq. 1 as a single measurement and record them in table 2 as the average value of n for each ray. NOTE: In Excel use the SIN function with thew angles in radians: SIN(RADlANS(6)). Repeat steps 3.1 to 3.4 for incident angles of about 50 and of about 70 with respect to the normal. Calculate the mean ii and the standard error S . E. = Standard Deviation/t Ht Ray Cases for the three measurements of index of refraction n and record them in table 2. In Excel the mean is calculated with the function AVERAGE(CeI|_1,...,Cell_N), the standard deviation with the function STDEV(Cell_1,...,CeII_N), and the square root with the function SQRT(Number of Ray cases). Table 2. Refraction in a prism Ray 91 62 03 64 n fl S . E . Refraction 3. Analysis 3.1. Are your data consistent with the law of reflection? 2. How precise is your value of n, the index of refraction of the prism? 3. Using the value of :1 determined for the prism, nd the speed of light in the prism. 4. Conclusions Based on data analysis, graphs, and results