



Unit 13 Quiz#3Equations:n_{i} x sin(Theta_{i}) = n _{r} x sin(Theta_{r})
4. Using complete sentences, describe the only condition in which light will pass across a boundary from one medium to another medium without undergoing refraction.
5. Light traveling through air (n = 1.00) is incident upon a triangular block (the triangle is equilateral; the sides make 60° angles with each other) made of an unknown material. The path of the light through the material is shown in the diagram below. Using a protractor and a calculator, determine the index of refraction of the unknown material. To receive credit, show the necessary measurements on the diagram and show all your work in the space below.
6. Define the term critical angle.
7. Determine the critical angle for an air (n=1.00)  glass (n=1.60) boundary. PSYW
8. In which of the following situations will total internal reflection occur if the incident angle is gradually increased? Circle the answers (Yes or No).
© Tom Henderson, 19961998 Last updated on
10/13/98. 