Section 26.4 Polarization and the Reflection and Refraction of Light

 25. A child is looking at a reflection of the sun in a pool of water. When she puts on a pair of Polaroid sunglasses with a vertical transmission axis, she can no longer see the reflection. At what angle is she looking at the pool of water?

(a) 45.0° (c) 53.1° (e) 77.3°

(b) 48.8° (d) 61.6°

 26. A ray of light originating in oil (n = 1.21) is incident at the Brewster angle upon a flat surface of

a quartz crystal (n = 1.458). Determine the angle of incidence for this ray.

(a) 0.82° (c) 40° (e) 56°

(b) 1.2° (d) 50°

 27. What is the Brewster angle if light is reflected from a plastic plate (n = 1.575) submerged in ethyl alcohol (n = 1.362)?

(a) 68.3° (c) 59.8° (e) 49.1°

(b) 40.8° (d) 30.1°

Questions 28 and 29 pertain to the following situation.

Light in air is incident on a plastic plate at the Brewster angle. The angle of refraction is 35.0°.

 28. Determine the Brewster angle.

(a) 35.0° (c) 46.5° (e) 82.3°

(b) 55.0° (d) 43.5°

 29. What is the index of refraction of the plastic plate?

(a) 1.58

(b) 1.36

(c) 1.43

(d) 1.61

(e) 1.74

Section 26.5 The Dispersion of Light: Prisms and Rainbows

 30. A ray of green light travels through air and is refracted as it enters a glass prism shown in the figure. An unknown liquid is in contact with the right side of the prism. The light then follows the path shown. Which one of the following statements concerning this situation is true?

(a) The frequency of the light changes inside the prism.

(b) The index of refraction of the glass is smaller than that of air.

(c) The index of refraction of the unknown liquid is the same as that of the glass.

(d) The speed of light is larger in the liquid than in the glass.

(e) The refractive index of the liquid is the same as that of air.

 31. Complete the following statement: The term dispersion refers to the fact that the index of refraction of certain materials

(a) depends on the Brewster angle. (d) depends on the intensity of light.

(b) depends on the wavelength of light. (e) depends on the polarization of light.

(c) depends on the angle of incidence.

 32. White light enters a glass prism, but the color components of the light are observed to emerge from the prism. Which one of the following statements best explains this observation?

(a) The separation of white light into its color components is due to the increase in the speed of light within the glass.

(b) Some of the color components of the white light are absorbed by the glass and only the remaining components are observed.

(c) The index of refraction of the glass depends on the wavelength, so the color components are refracted at different angles.

(d) Only some of the color components are refracted by the glass; and these are the ones that are observed.

(e) White light is separated into its color components by total internal reflection within the prism.