Waves, Sound, and Light Name:______
Unit Exam Period:____
Multiple Choice: (80 points / 1 point each): Circle the correct answer
1. The source of all wave motion is a…
a. / region of variable high and low pressure.b. / vibration.
c. / movement of matter.
d. / harmonic object.
2. The time needed for a wave to make one complete cycle is its…
a. / frequency.b. / velocity.
c. / amplitude.
d. / period.
3. The distance between successive identical parts of a wave is called its…
a. / frequency.b. / period.
c. / amplitude.
d. / wavelength.
4. The Hertz is a…
a. / special radio wave.b. / unit of period.
c. / unit of wavelength.
d. / unit of frequency.
5. A wave created by shaking a rope up and down is called a…
a. / Doppler wave.b. / standing wave.
c. / longitudinal wave.
d. / transverse wave.
6. Which of the following is NOT a transverse wave?
a. / lightb. / radio wave
c. / sound
d. / all of the above
7. When you increase the frequency of a sound wave…
a. the period will also increase. c. pitch will decrease.
b. the period will decrease . d. loudness will increase.
8. Sound waves…
a. / are a part of the electromagnetic spectrum.b. / do not require a medium for transmission.
c. / are longitudinal waves.
d. / are transverse waves.
9. Mechanical waves can NOT transport…
a. energy c. matter
b. material d. answers b and c are correct
10. Compared to the speed of light, sound travels…
a. / faster.b. / at about the same speed.
c. / slower.
11. Sound waves cannot travel in…
a. / steel.b. / air.
c. / a vacuum.
d. / water.
Answer questions 12 – 15 based on the wave-form below. The wave was produced when a student sings a tune for 0.03 seconds. Assume the speed of sound in air is 320 m/s.
12. How many full waves are there?
a. 11 b. 12 c. 13 d. 6
13. What is the waves frequency?
a. 400 hz b. 366 hz c. 120 hz d. 40 hz
14. What is the waves period?
a. 1/400 s b. 1/120 s c. 1/366 s
15. What is its wavelength?
a. 0.8 m b. 12 m c. 8 m d. 80 m
16. How high or low we perceive a sound to be, depending on the frequency of the sound wave, is defined as the…
a. / amplitude. / c. / ultrasonic wave.b. / resonance. / d. / pitch.
17. If you double the frequency of a vibrating object, its period…
a. / halves.b. / is quartered.
c. / doubles.
18. A 680-Hz sound wave travels at 340 m/s in air, with a wavelength of…
a. / 0.5 m.b. / 5 m.
c. / 50 m.
d. / 500 m.
19. The speed of wave depends on…
a. / the temperature of the medium.b. / the elasticity of the medium.
c. / its wavelength.
d. / its frequency.
20. A boy standing 100 m in front of a cliff and yells. If he hears his echo after 0.6 seconds, what is the speed of sound in air?
a. 333.3 m/s b. 166.7 m/s c. 340 m/s d. 100 m/s
21. The region of highly spaced particles on a longitudinal wave are referred to as…
a. crests. b. compressions. c. antinodes. d. rarefactions.
22. The period of an ocean wave is 10 seconds. What is the wave’s frequency?
a. / 0.10 Hzb. / 5.0 Hz
c. / 10.0 Hz
d. / 20.0 Hz
23. A certain ocean wave has a frequency of 0.07 hertz and a wavelength of 10meters. What is the wave’s speed?
a. / 0.07 m/sb. / 0.70 m/s
c. / 1.0 m/s
d. / 10 m/s
24. Sound travels faster in water than…
a. / steel.b. / air.
c. / aluminum.
25. When two or more waves are at the same place at the same time, the resulting effect is called…
a. / a Doppler wave.b. / a shock wave.
c. / interference.
d. / a period.
26. Which of the following types of interference will occur in the figure below?
a. / constructive / c. / complete destructiveb. / partial destructive / d. / complete longitudinal
27. Noise-canceling earphones are an example of…
a. / constructive interference.b. / destructive interference.
c. / beats.
d. / resonance.
28. Two waves arrive at the same place at the same time exactly in step with each other. Each wave has an amplitude of 2.5 m. The resulting wave has an amplitude of…
a. 0.6 m. b. 1.3 m. c. 2.5 m. d. 5.0 m.
29. The apparent rise and fall of frequency due to the motion of the wave source or observer is called…
a. constructive interference . c. The Doppler effect
b. refraction. d. beats.
30. Suppose a bug is jiggling up and down and swimming towards you at the same time. Compared to the frequency at which the bug is emitting waves, the frequency of the waves reaching you is…
a. / lower.b. / higher.
c. / just the same.
31. Which observer would hear the louder sound?
a. The lady b. The man c. They both do
32. Roughly how many times faster than the speed of sound is the plane traveling?
a. 1 b. 2 c. 3 d. 4
33. A sonic boom…
a. / is swept continuously behind a plane flying faster than the speed of sound.b. / is produced only as a plane breaks through the sound barrier.
c. / is produced by subsonic projectiles as well as subsonic aircraft.
d. / none of the above
34. How many nodes and antinodes are shown in the standing wave below?
a. / four nodes and four antinodes / c. / four nodes and five antinodesb. / four nodes and three antinodes / d. / five nodes and four antinodes
Answer questions 35-38 based on the following standing wave diagram:
35. How many nodes are there?
a. 6 b. 7 c. 5 d. none
36. How many full waves are there?
a. 3 b. 6 c. 1.5 d. none
37. What is its the wavelength?
a. 3 m b. 9 m c. 6 m d. 2-m
38. What is the waves amplitude?
a. 10 cm b. 5 cm c. 30 cm d. 3 m
39. Where can you touch a standing wave on a rope without disturbing the wave?
a. / At a nodeb. / At any place along the wave
c. / At an antinode
40. What is it called when a body is forced to vibrate at its natural frequency?
a. Forced vibration c. Doppler effect
b. Resonance d. Beats
41. A singer shattering crystal glass with her voice is a demonstration of…
a. / resonance.b. / sound refraction.
c. / an echo.
d. / interference.
42. Suppose three tuning forks of frequencies 660 Hz, 662 Hz and 666 Hz are available. What beat frequencies are possible for pairs of these forks sounded together?
a. 2 hz b. 4 hz c. 6 hz d. answers a, b and c
43. Which of these electromagnetic waves has the shortest wavelength?
a. Infrared waves b. Light waves c. Radio waves d. X-rays
44. Compared to the velocity of radio waves, the velocity of visible light waves is…
a. slower. b. faster. c. the same.
45. Which of the following are fundamentally different from the others?
a. Gamma rays b. Radio waves c. Sound waves d. Light waves
46. If the sun were to disappear right now, we wouldn't know about it for 8 minutes because it takes 8 minutes…
a. to operate receiving equipment in the dark.
b. for light to travel from the sun to Earth.
c. for the sun to disappear.
d. all of the above
47. The vibrations of these cause the emission of light…
a. protons. b. electrons.
c. neutrons. d. answers a and c are correct
48. Light travels in discrete packets of energy called…
a. electrons. b. quarks. c. photons. d. protons.
49. Glass is transparent to visible light, but not to…
a. ultraviolet. b. infrared. c. both a and b d. none of the above
50. The three primary colors of light for additive color mixing are…
a. red, green, and blue. b. yellow, green, and blue.
c. red yellow, and blue d. red, yellow, and green
51. When red and blue light shine on a white sheet, the resulting color is…
a. yellow. b. blue. c. cyan. d. green. e. magenta.
52. When red and green light shine on a white sheet, the resulting color is…
a. blue. b. green. c. yellow. d. magenta. e. cyan.
53. The cyan color of ocean water is evidence that the water absorbs…
a. yellow. b. green. c. orange. d. blue. e. red.
54. Compared to its speed in air, the speed of light in water is…
a. slower. b. the same. c. faster.
55. Which of the following is not a primary pigment?
a. red b. yellow c. cyan d. magenta
56. The complementary color of green is…
a. green. b. red. c. magenta. d. cyan.
57. The combination of all colors produces…
a. brown. b. black. c. magenta. d. white.
58. The absence of color is…
a. a secondary color. b. a primary color.
c. black. d. white.
59. Different colors of light travel at different speeds in a transparent medium. In a vacuum, different colors of light travel at…
a. the same speed. b. different speeds. c. do not travel
60. The color of an opaque object is determined by the light that is…
a. refracted. b. reflected. c. transmitted. d. all of the above
61. What type of light source produces light due to heat?
a. incandescent b. fluorescent c. transparent d. opaque
62. The speed of light is…
a. 300,000 m/s c. 3 x 108 m/s
b. 340 m/s d. answers a and b are correct
63. Why do glass lens sunglasses reduce the intensity of light?
a. opaqueness to infrared light b. polarization of light
c. opaqueness to visible light d. answers a and c are correct
64. Light typically travels faster through…
a. air. b. glass. c. water. d. a vacuum.
65. Materials that selectively reflect and absorb colors based on frequency are called…
a. transparent. b. luminous. c. pigments. d. rarefactions.
66. The region of total shadow is referred to as the…
a. umbra. b. penumbra . c. eclipse. d. pigment.
67. A ray of light strikes a mirror at an angle of 23o to the normal. What is the angle between the incident and the mirror?
a. 23o b. 46o c. 67o d. -23o
68. Suppose you stand 2 m in front of a plane mirror. How far away from you is your image?
a. 4m. b. 1/2m. c. 1m. d. 2m.
69. The image produced by a plane mirror is…
a. real b. virtual c. magnified d. inverted
70. The bending of light as it encounters a boundary is called…
a. refraction. b. interference. c. diffraction. d. polarization.
71. What type of images cannot be formed on a screen?
a. real b. virtual c. both d. neither
72. What color of light is most deviated by our atmosphere?
a. red b. blue c. green d. violet
73. Light waves have a frequency of 3.3 x 1014 hz. If the speed of light is 3 x 108 m/s, what is light’s wavelength?
a. 1.0 x 1023 m b. 9 x 10-6 m c. 0.9 x 10-6 m d. 0.6 x 108 m
74. When a virtual image is created in a plane mirror…
a. the image is upright. b. the image is located behind the mirror.
c. reflected rays diverge. d. all of the above
75. Refraction is caused by…
a. waves encountering a gap. b. more than one reflection.
c. displaced images. d. changing waves speeds at a boundary.
76. Refraction…
a. can occur when a wave changes speed. b. can not occur at a boundary
c. only occurs with mechanical waves d. only occurs with light waves
77. A penny lies in the bottom of a tea cup filled with water. As you look down on the penny, compared to its actual depth, it looks…
a. / closer.b. / farther away.
c. / at the same depth.
78. When a wave passes through an opening, some of the wave is bent. This phenomenon is called…
a. polarization. b diffraction. c. refraction. d. interference.
79. Colors seen when gasoline forms a thin film on water are a demonstration of…
a. refraction. b. diffraction. c. dispersion. d. interference.
80. Which of the following travel at the speed of light?
a. x-rays b. microwaves
c. radio waves d. answers a, b and c are correct