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1. A flashlight is directed at the flat side of a piece of glass with an index of refraction of 1.50. The light travels through air. Calculate the angle of incidence that results in perfectly polarized light. What is the name of this angle? (4 marks) 2. Light travels from air into a transparent material that has an index of refraction of 1.4. The angle of refraction is 50. (a) Calculate the angle of incidence. (b) Determine the critical angle for total internal reflection to occur in the transparent material. (6 marks)3. A group of students uses an intense white light and a red filter to create bright fringes in a double-slit experiment. Describe the differences in the observed results when the students make the following changes, and explain the differences. (a) Move the screen closer towards the slits. (b) Replace the red filter with a blue filter. (5 marks) 4. Suppose a monochromatic light incident on a single slit produces a diffraction pattern. (a) How would the pattern differ if you decrease the wavelength of the light by half? (b) How would the pattern differ if you tripled both the wavelength and slit width at the same time