Sounds in Strings

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Sounds in Strings
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Warm- Up

• Write a caption for the cartoon.
• What do you think?
• How do guitarists or violinist today make
  different sounds.

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Record the results in your table
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Parts of a Wave
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Review Sounds in Strings
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Acoustic Waves

• When the string in a musical instrument vibrates,
  it moves in a combination, or superposition, of
  many standing wave patterns. A guitarist can
  suppress certain of these standing waves to
  emphasize the remaining ones by making chimes.
  The technique is to simultaneously pluck the
  string and lightly tap it at the right spot for
  the particular chime.

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Review Questions

• What kind of wave is a sound wave? (longitudinal
  / transverse)
• What is another name for sound waves?
• Acoustics
• Can sounds travel through a vacuum?
• No

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Homework

• Add the Physics words
• Read Changing the Pitch pg. 197
• Answer Physics to Go pg. 198 1-7

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Sound in String Debrief

• 4a. What happened when you pressed down on the
  string right in the middle? (1pt)
• 5a. Look at the data on your table. What was
  the relationship between the length of the string
  and what you heard? (2pts)

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Sounds in Strings Debrief Continued

• 7b. Describe what happened as you added mass to
  the string. (2pts)
• 7c. What happens to the pitch when you tighten
  the string? (2pts)
• Write a conclusion- What did you learn?

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• How did we determine the wavelength of the wave?
• 6b. What is the relationship between the
  wavelength of the string and the pitch? (2pts)

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How we hear sound

• In perceiving sound, the human eardrum vibrates
  in response to the pattern of high and low
  pressure. This vibration is translated into a
  signal transmitted by the nervous system to the
  brain and interpreted by the brain as the
  familiar sensation of sound.