TEACHER ANSWER KEY
June 02, 2004
Wavy 5-13-03
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1. Which diagram best represents the reflection of light from an irregular
surface?
1. 1
2. 2
3. 3
4. 4
No Explanation Available.
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2. In a vacuum, a monochromatic beam of light as a frequency of 6.3 X 1014
hertz. What color is the light?
1. red
2. yellow
3. green
4. blue
No Explanation Available.
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3. A beam of light crosses a boundary between two different media. Refraction
can occur if
1. the angle of the incidence is 0
degrees
2. there is no change in the speed of
the wave
3. the media have different indices off
refraction
4. all of the light is reflected
No Explanation Available.
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4. The diagram shows with light being dispersed as it passes from air into a
glass prism. This phenomenon occurs because, in glass, each frequency of light
has a different
1. intensity
2. amplitude
3. angle of incidence
4. absolute index of refraction
No Explanation Available.
2
5. The distance from the Moon to the Earth is 3.9 X 108 meters. What is the
time required for a light ray to travel from the Moon to Earth?
1. 0.65 s
2. 1.3 s
3. 2.6 s
4. 3.9 s
No Explanation Available.
3
6. Parallel light rays are incident on the surface of a plane mirror. Upon
reflection from the mirror, the light rays will
1. converge
2. diverge
3. be parallel
4. be scattered
No Explanation Available.
4
7. In the diagram, a ray of monochromatic light reaches the boundary between
medium X and air and follows the path shown. Which medium is most likely
medium X?
1. Diamond
2. flint glass
3. Lucite
4. water
No Explanation Available.
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8. Which phenomenon can not be exhibited by longitudinal waves?
1. reflection
2. refraction
3. diffraction
4. polarization
No Explanation Available.
2
9. A ray of light traveling in crown glass is incident on a diamond interface at
an angle of 30', as shown in the diagram. The angle of refraction for the light
ray is closest to
1. 12'
2. 18'
3. 30'
4. 53'
No Explanation Available.
2
10. As the color of light changes from red to yellow, the frequency of the light
1. decreases
2. increases
3. remains the same
No Explanation Available.
1
11. If all parts of a light beam have a constant phase relationship, with the same
wavelength and frequency, the light beam is
1. monochromatic and coherent
2. monochromatic and incoherent
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3. polychromatic and coherent
4. polychromatic and incoherent
12. A monochromatic beam of light has a frequency of 6.5 × 1014 hertz. What
color is the light?
1. yellow
2. orange
3. violet
4. blue
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13. What is the measure of the angle of refraction? [Use a protractor or a
mathematical calculation.]
1. 19°
2. 30.°
3. 49o
4. 60.°
2
14. The speed of the light in Lucite is
1. 1.5 × 108 m/s
2. 2.0 X 108 m/s
3. 3.0 × 108 m/s
4. 4.5 × 108 m/s
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15. The critical angle for the Lucite-air boundary is approximately
1. 67°
2. 48°
3. 42o
4. 33°
3
16. A light ray is incident on a plane mirror as shown in the diagram.
Which ray best represents the reflected ray?
1. A
2. B
3. C
4. D
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17. What occurs as a ray of light passes from air into water?
1. The ray must decrease in speed.
2. The ray must increase in speed.
3. The ray must decrease in frequency.
4. The ray must increase in frequency.
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18. The diagram shows a ray of light passing from medium X into air. What is
the absolute index of refraction of medium X?
1. 0.05
2. 2.0
No Explanation Available.
1
3. 1.7
4. 0.58
19. In the diagram, a ray of monochromatic light (A) and a ray of
polychromatic light (B) are both incident upon an air-glass interface. Which
phenomenon could occur with ray B, but not with ray A?
1. dispersion
2. reflection
3. polarization
4. refraction
No Explanation Available.
3
20. If the critical angle for a substance is 44'. the index of refraction of the
substance is equal to
1. 1.0
2. 0.69
3. 1.4
4. 0.023
No Explanation Available.
2
21. The diagram represents the path of periodic waves passing from medium A
into medium B. As the waves enter medium B, their speed
1. decreases
2. increases
3. remains the same
No Explanation Available.
4
22. A beam of green light may have a frequency of
1. 5.0 X 10-7 Hz
2. 1.5 X 102 Hz
3. 3.0 X 108 Hz
4. 6.0 X 1014 Hz
1
23. Compared to wavelengths of visible light, the wavelengths of ultraviolet
light are
1. shorter
2. longer
3. the same
1
24. The accompanying diagram shows a ray of light passing through two
media.
When the wave travels from medium A into medium B, its speed
1. decreases
2. increases
3. remains the same
4
25. The accompanying diagram shows light rays in air about to strike a glass
window.
When the rays reach the boundary between the air and the glass, the light is
1. totally refracted
2. totally reflected
3. partially reflected and partially
diffracted
4. partially reflected and partially
refracted
1
26. Which diagram best illustrates wave diffraction?
1
27. Which diagram best represents the path of light rays passing through a glass
prism?
1
28. A ray of monochromatic light traveling in air enters a rectangular glass
block obliquely and strikes a plane mirror at the bottom. Then the ray travels
back through the glass and strikes the air-glass interface. Which diagram best
represents the path of this light ray? [N represents the normal to the surface.]
1
29. A ray of monochromatic light is traveling in flint glass. The ray strikes the
flint glass-air interface at an angle of incidence greater than the critical angle
for flint glass. Which diagram best represents the path of this light ray?
4
30. A ray of light strikes a plane mirror at an angle of incidence equal to 35o.
The angle between the incident ray and the reflected ray is
1. 0o
2. 35o
3
3. 55o
4. 70.o
31. A ray of light ( = 5.9 X 10-7 meter) traveling in air is incident on an
interface with medium X at an angle of 30.o. The angle of refraction for the
light ray in medium X is 12.o. Medium X could be
1. alcohol
2. corn oil
3. diamond
4. flint glass
1
32. The diagram shows a ray of monochromatic light incident on an alcoholflint glass interface. What occurs as the light travels from alcohol into flint
glass?
1. The speed of the light decreases and
the ray bends toward the normal.
2. The speed of the light decreases and
the ray bends away from the normal.
3. The speed of the light increases and
the ray bends toward the normal.
4. The speed of the light increases and
the ray bends away from the normal.
No Explanation Available.
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33. The diagram shows straight wave fronts passing through an opening in a
barrier. This wave phenomenon is called
1. reflection
2. refraction
3. polarization
4. diffraction
No Explanation Available.
1
34. The absolute index of refraction for a substance is 2.0 for light having a
wavelength of 5.9 x 10-' meter. In this substance, what is the critical angle for
light incident on a boundary with air?
1. 30
2. 60'
3. 450'
4. 90'
No Explanation Available.
3
35. A ray of monochromatic light (wavelength= 5.9 x 10-7 meter) traveling in
air is incident on an interface with a liquid at an angle of 45", as shown in the
diagram below. If the absolute index of refraction of the liquid is 1.4, the angle
of refraction for the light ray is closest to
1. 10.0'
2. 20.0'
3. 30.0'
4. 40.0'
No Explanation Available.
2
36. Which phenomenon can occur with light, but not with sound?
1. interference
2. polarization
No Explanation Available.
3. refraction
4. the Doppler effect
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37. Which diagram best represents light emitted from a coherent light source?
No Explanation Available.
2
38. The speed of light in glycerol is approximately
1. 1.0 x 107 m/s
2. 2.0 x 108 m/s
3. 3.0 x 108 m/s
4. 4.4 x 108 m/s
No Explanation Available.
1
39. Light travels through a solution. If the absolute index of refraction of the
solution is increased, the critical angle will
1. decrease
2. increase
3. remain the same
No Explanation Available.
4
40. A beam of monochromatic light crosses a boundary from air into Lucite at
an angle of incidence of 45'. The angle of refraction is approximately
1. 63'
2. 56'
3. 37'
4. 28'
No Explanation Available.
1
41. The speed of light in a material is 2.5 x 108 meters per second. What is the
absolute index of refraction of the material?
1. 1.2
2. 2.5
3. 7.5
4. 0.83
No Explanation Available.
1
42. A laser beam does not disperse as it passes through a prism because the
laser beam is
1. monochromatic
2. polychromatic
3. polarized
4. longitudinal
No Explanation Available.
2
43. In the diagram, monochromatic light in air is about to travel through crown
glass, water, and diamond. In which substance does the light travel the slowest?
1. air
2. diamond
No Explanation Available.
3. water
4. crown glass