Download Chapter 21 Notes - Caching in with GPS

Name _______________________________ Date __________
Chapter 21: Sound
1. The loudness of sound comes from the _______________ of a sound wave.
2. The _______________ of a sound is how you hear its frequency.
3. The range of frequencies humans can hear is from ______ Hz to __________ Hz.
4. The sound of the human voice contains ______________ of different frequencies.
5. A graph that shows the different frequencies in a sound is called a
_______________ _______________.
6. The loudness of a sound is measured in _______________.
7. Fill in the following decibel chart.
0 dB
10-15 dB
30-40 dB
45-55 dB
65 dB
70 dB
90 dB
100 dB
110 dB
120 dB
8. The human ear is most sensitive to sound between _____ Hz and ________ Hz.
9. An _______________ _______________ curve compares how loud you hear
sounds of different frequencies.
10. Sounds near _______________ Hz seem louder than sounds at other frequencies.
11. The science and technology of sound is called _______________.
12. The speed of sound in air is around _______ meters per second ( ______ mph).
13. Objects that move slower than sound are said to be _______________, while
those that travel faster than sound are called _______________.
14. A supersonic jet causes a cone-shaped _______________ _______________ to
form. Right at the shock wave, you can hear a _______________ ____________.
15. Sound travels about _______ times faster in water than in air.
16. The shift in frequency caused by motion is called the _______________ Effect.
17. The Doppler Effect only happens when the source is _______________.
(subsonic or supersonic)
18. A microphone transforms a sound wave into an _______________ signal.
19. An analog to digital converter measures the electrical signal _______________
times per second! The numbers are recorded as data on a _______________.
20. In order to play the music back, you need a _______________ to
_______________ converter.
21. A _______________ recording is two recordings, one for the left ear and one for
the right.
22. Sound is a _______________ wave because the air is compressed in the same
direction the wave travels.
23. When music is playing, the cone of a speaker creates a _______________
_______________ of alternating high and low pressure.
24. In air, the _______________ of a sound wave is carried by moving molecules.
25. When air is cold, the speed of sound _______________.
26. If the air pressure goes up, the speed of sound _______________.
27. The speed of sound is _______________ in helium, which is why your voice
sounds funny if you inhale helium.
28. The wavelength of sound is _______________ related to its frequency.
29. A long tube makes a _______________ frequency sound, while a short tube
makes a _______________ frequency sound.
30. To make a high frequency sound on a guitar string, you need to make the string
_______________ (longer or shorter?)
31. Reflected sound and direct sound create a multiple echo called ______________.
32. Reverberation also causes _______________ of sound waves.
33. _______________ _______________ are areas where _______________
interference causes sound to cancel with its own reflections.
34. Spaces enclosed by boundaries can create _______________ with sound waves.
35. In a closed pipe, the closed end is a _______________ in the standing wave,
while the open end is an _______________.
36. The wavelength of the _______________ is ______ times the length of the pipe.
37. Almost all the sound you hear is a combination of _______________.
38. _______________ theorem says that a wave of any shape can be made by adding
up _______________ frequency waves. This is based on the _______________
principle.
39. When you hear a sound, the nerves in you ear respond to more than
_______________ different frequencies at the same time!
40. Your ear is a living application of _______________ theorem; it separates the
sound into different _______________.
41. A _______________ _______________ is a graph showing the different
frequencies present in a sound.
42. The _______________ axis tells you the loudness and the _______________ axis
tells you the frequency.
43. Both the _______________ _______________ and the _______________ change
as the sound changes.
44. A _______________ shows how loud sound is at different frequencies over a
period of time.
45. A sonogram shows _______________ on the vertical axis and _______________
on the horizontal axis. The _______________ is shown by different colors.
46. We get our sense of hearing from the _______________.
47. The cochlea also gives us our sense of _______________.
48. The _______________ vibrates in response to sound waves in the ear canal.
49. The nerves near the large end of the cochlea respond to ____________ frequency
sound while those near the small end respond to _______________ frequencies.
50. People gradually lose the ability to hear _______________ frequency sounds.
51. Listening to loud music can cause the tiny _______________ in your cochlea to
weaken or break off.
52. The _______________ of a sound is how high or low we hear the frequency.
53. _______________ is a regular time pattern in a sound.
54. Rhythm can be made with sound and silence, or with different _______________.
55. A combination of pitch and rhythm that we like is called _______________.
56. Music is created from a pattern of frequencies called a _______________
_______________. Each frequency is called a _______________.
57. The range between a _______________ and twice that frequency is called an
_______________.
58. _______________ is the study of how sounds work together to create effects, and
is based on the _______________ relationships of the musical scale.
59. When two frequencies are close, but not equal, the sounds seem to oscillate or
_______________. This is helpful in _______________ a musical instrument.
60. If the combination of sounds is pleasing, it is called _______________. If it is
not pleasing, it is called _______________.
61. _______________ _______________ are folds of extendable tissue.
62. The vocal cords extend across a hollow chamber called the _______________.
63. Guitars make sounds by _______________ strings.
64. The guitar is tuned by changing the _______________ of the strings.
65. A guitar with 20 frets and 6 strings can make _______________ different notes.
66. The sound from an _______________ is NOT a single pure frequency.
67. The variation in sound comes from the _______________, frequencies that are
multiples of the _______________ note.