Index of Refraction and Snell's Law n = n1 sine 1 = n2 sine2 1) What is the effective speed of light when passing through Media Index of Refraction common table salt? Vacuum 1.00 Air 1.0003 Carbon dioxide gas 1.0005 Ice 1.31 Pure water 1.33 Ethyl alcohol 1.36 Quartz 1.46 Vegetable oil 1.47 Olive oil 1.48 Acrylic 1.49 Table salt 1.51 2) Suppose you have an unknown clear substance immersed Glass 1.52 in pure water, and you wish to identify it by finding its index Sapphire 1.77 of refraction. You arrange to have a beam of light enter it Zircon 1.92 Cubic zirconia 2.16 at an angle of 45.0, and you observe the angle of refraction Diamond 2.42 to be 40.30. What is the index of refraction of the substance Gallium phosphide 3.50 and its likely identity? Total Internal Reflection 3) At what critical angle will you get total internal reflection of light traveling in water and reflected from ice? (Remember: critical angle is the angle of incidence when the angle of refraction equals 90%)