1. A woman 168cm tall stands in front of a plane mirror attached to a vertical wall. What is the minimum length that the mirror must have for the woman to see her entire height?
2. Water in a fish tank is 38cm deep, and a coin rests on the bottom. How far below the surface does the coin appear to be when viewed from above? (Assume a small angle of incidence.)
3. A fish tank filled with water is made of flat glass walls of n = 1.50. What is the maximum angle of incidence for a light ray within the water to strike the glass wall and still emerge to the outside air?
4. beam of light in air is incident at an angle of 45 degrees on the surface of a transparent solid. The light is deviated by 18 degrees toward the normal upon entering the solid. What is the critical angle for total internal reflection from within this solid?