114: Using Sound

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11-4 Using Sound

• Workbooks openeveryone answers!

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Acoustics

• ______ is the echoing effect caused by many
  reflections of sound.
• reverberation
• Why can reverberation be a problem in a concert?
• The reverberation can overwhelm the music itself!
• Define the science of acoustics
• This is the study of sound.
• Name some ways that an acoustical engineer might
  cut down on the reverberation in a concert hall?
• Walls and floors carpeted, seats padded, avoid
  hard surfaces, avoid angles that create strange
  reflections

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Echolocation

• What animal uses echolocation?
• Bats, dolphins
• Why do they use it?
• Because they hunt at night, and their eyes arent
  as useful in the dark.
• How does echolocation work?
• The bat squeaks out very high frequencies. These
  frequencies hit moths or other objects and are
  reflected. The bat hears the echoes and
  interprets them to make a mental picture of what
  is in front of it.

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Sonar

• Sonar uses ______ ______ ______ waves to detect
  objects.
• Underwater sound waves
• How is sonar like echolocation?
• Both concepts produce sound waves that reflect to
  the listener and are interpreted.
• How are sonar and bat echolocation different?
• Sonar uses water as a medium and echolocation
  uses air as a medium.

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Ultrasound in medicine

• Why do jewelers use ultrasound?
• To break up dirt on jewelry
• Why do doctors use ultrasound?
• To see inside a persons body to help diagnose or
  treat medical conditions.
• How is medical ultrasound similar to echolocation
  and sonar?
• All three use sound waves that are emitted and
  reflected. All three interpret the reflected
  sound waves into a picture
• How is medical ultrasound different from sonar?
• In sonar, the medium is water. In ultrasound,
  the medium is the human body.
• How can ultrasound help with kidney stones?
• The ultrasound waves can break the kidney stones
  up and the patient can avoid surgery.

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Echolocation
Echolocation
Echolocation
http//research.amnh.org/users/nyneve/bats.html
http//www.wdcs.org/dan/imagelib.nsf/graphics/aad2
/file/echolocation.gif
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Sonar
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Ultrasound
http//www.medgadget.com/archives/img/4D.jpg