Aim: How can we apply refraction to a laser beam through a glass block? HW:

Procedure: Trace the block on a sheet of paper Remove the block and construct a normal line close to the upper right hand corner Using colored pencils, construct 5 incident rays at various angles between 15o and 60o Replace the block, and using a ruler like the mirror lab, sight one of the incident rays through the block such that the ruler’s edge would run straight with the ray. Trace that ray and repeat for all 5 rays Remove the block and connect the rays of the same color measure the angle of refraction for each incident ray at the top of the block Construct normal lines at each exit point and measure the incident and refracted angles. Enter all angles in the data table Graph sin θ1 vs. sinθ2 (what will the slope of this graph be?)

Do Now!

Finding the Index of Refraction Goals: The goals of this lab include to determine the index of refraction of the unknown block using a graph Background write a PARAGRAPH explaining how refraction works and what happens to all the parameters (speed, wavelength, frequency) of a light wave as it moves from one medium to another. Procedure based on the do now graph, what do we need to do to determine the index of refraction of a block?

Finding the Index of Refraction Normal line Incident rays. 15o increments Refraction Block Top view Just like in the mirror lab, you will use a ruler to line up the ray while looking THROUGH the block. You line of sight needs to be at table level! You can use pins to help you line it up. Focus on ONE color at a time

Lab Requirements Each person needs A goal statement Background PARAGRAPH on refraction and how it works A procedure Well organized data table (similar to the do now) Graph Slope calculation and percent error Conclusion PARAGRAPH

Summary How did the light bend upon entering the glass? Upon entering the glass, what happened to the lights speed? What was the slope of your graph and why? What was the angle of the light coming out of the glass?