# Unit 13 Review

Reflection and Refraction

 Navigate to Answers for: [ Questions #1-#12 | Questions #13-#24 | Questions #25-#36 | Questions #37-#49 ] [#25 | #26 | #27 | #28 | #29 | #30 | #31 | #32 | #33 | #34 | #35 | #36 ]

25. A light ray in air is incident on an air to glass boundary at an angle of 45 degrees and is refracted in the glass of 30 degrees with the normal. What is the index of refraction of the glass?
 a. 2.13 b. 1.74 c. 1.23 d. 1.41

Determination of n Values (10 seconds)

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26. A beam of light in air is incident at an angle of 35 degrees to the surface of a rectangular block of clear plastic (n = 1.49). The light beam first passes through the block and re-emerges from the opposite side into air at what angle to the normal to that surface?
 a. 42 degrees b. 23 degrees c. 35 degrees d. 59 degrees

Snell's Law (10 seconds) | Ray Tracing and Problem-Solving (15 seconds)

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27. A light ray in air enters and passes through a block of glass. What can be stated with regard to its speed after it emerges from the block?

 a. speed is less than when in glass b. speed is less than before it entered glass c. speed is same as that in glass d. speed is same as that before it entered glass

Optical Density and Light Speed (13 seconds)

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28. Which of the following describes what will happen to a light ray incident on an air-to-glass boundary?

 a. total reflection b. total transmission c. partial reflection, partial transmission d. partial reflection, total transmission

Boundary Behavior Revisited (5 seconds) | Total Internal Reflection (13 seconds)

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29. Which of the following describes what will happen to a light ray incident on an air-to-glass boundary at less than the critical angle?

 a. total reflection b. total transmission c. partial reflection, partial transmission d. partial reflection, total transmission

Boundary Behavior Revisited (5 seconds) | Total Internal Reflection (13 seconds)

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30. Which of the following describes what will happen to a light ray incident on an glass-to-air boundary at greater than the critical angle?

 a. total reflection b. total transmission c. partial reflection, partial transmission d. partial reflection, total transmission

Boundary Behavior Revisited (5 seconds) | Total Internal Reflection (13 seconds)

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31. What is the angle of incidence on an air-to-glass boundary if the angle of refraction in the glass (n = 1.52) is 25 degrees?

 a. 16 degrees b. 25 degrees c. 40 degrees d. 43 degrees

Snell's Law (10 seconds) | Ray Tracing and Problem-Solving (15 seconds)

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32. A ray of white light, incident upon a glass prism, is dispersed into its various color components. Which one of the following colors experiences the greatest amount of refraction?

 a. orange b. violet c. red d. green

33. When light from air hits a smooth piece of glass (n = 1.5) with the ray perpendicular to the glass surface, which of the following will occur?

 a. reflection and transmission at an angle of 0 degrees b. dispersion c. refraction at an angle of 41.8 degrees d. all of the above will occur

Boundary Behavior Revisited (5 seconds) | Total Internal Reflection (13 seconds)

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34. When light from air hits a smooth piece of glass with the ray perpendicular to the glass surface, the part of the light passing into the glass

 a. will not change its speed b. will not change its direction c. will not change its wavelength d. will not change its intensity

The Secret of the Archer Fish (8 seconds)

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35. If total internal reflection occurs at a glass-air surface,

1. no light is refracted
2. no light is reflected
3. light is leaving the air and hitting the glass with an incident angle greater than the critical angle
4. light is leaving the air and hitting the glass with an incident angle less than the critical angle

Total Internal Reflection (13 seconds)

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36. Dispersion occurs when

1. some materials bend light more than other materials
2. a material slows down some colors more than others
3. a material changes some colors more than others
4. light has different speeds in different materials