Sound

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Sound

• Music to my ears!

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Sound Study Guide
Click on your study guide choice!
What is sound?
Pitch vs. Volume
How we hear sound
Videos from class
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What is Sound?

• Sounds are vibrations

Like in our investigations, this ruler shows how
objects that make sound make vibrations. Air
molecules vibrate and send these vibrations to
your ear where you hear the sounds!
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What is Sound?

• Sounds travel in waves

Each wave represents a sound wave. Remember
that the molecules vibrate and pass on the
vibrations to the molecules around them to move
the wave to your ear!
http//odin.physastro.mnsu.edu/eskridge/astr101/S
urface_waves.jpg
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Sound through materials

• Sounds pass through denser forms of matter better
• Click here to visit a site on sound and matter
  density!

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Review Questions

• If an object does NOT vibrate, will it make a
  sound?

Yes
No
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Review Question

• What material does sound travel through the best?

Solid
Liquid
Gas
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Correct!

• Sounds travel through denser forms of matter like
  solids because the molecules are closer together
  and the vibrations get passed on faster!

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Correct!

• Even if you cannot see the vibrations, anything
  that makes a sound HAS to vibrate!

Great Job! Move onto the next study guide!
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Nice try, but lets review!
Lets review now!
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Great Job!

• Lets go back and pick another review topic!

Pick another review topic now!
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Pitch Versus Volume

• Whats the difference?

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Pitch vs. Volume

• Pitch is how HIGH or LOW a sound is
• Listen to the differences from our nail pitch
  investigation!

Listen
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Pitch
Pitch is the speed of vibrations

• The FASTER the vibrations (higher frequency)
• The HIGHER the pitch

• The SLOWER the vibrations (lower frequency)
• The LOWER the pitch

High Frequency/pitch
Low Frequency/pitch
http//www.sciencenewsforkids.org/articles/2008101
5/Feature1.asp
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Changing Pitch

• Think back to our pitch investigations
• Changing the length of a ruler
• Changing the length of the string
• Changing the length of the slide whistle
• What does changing length do to pitch?
• The shorter the length, the higher the pitch
• The longer the length, the lower the pitch!

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Tension

• Like the string board, changing the TENSION in a
  string will change the pitch.
• INCREASING the tension (making it tighter) will
  INCREASE the pitch.
• DECREASING the tension (making it looser) will
  DECREASE the pitch.

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Think Back

• What was ONE way we changed pitch in our
  investigations?

Shorten the string or column of air
Hit the drum with more force
Add more strings of the same length
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Correct!

• To make the pitch HIGHERSHORTEN the string or
  instrument!
• To make the pitch LOWERLENGTHEN the string or
  instrument!

Next Question!
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Nice try but lets review!
Review now!
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Next Question

• From our investigation with our string boards,
  loosening the string (decreasing tension) will

Make the pitch HIGHER
Make the pitch LOWER
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Correct!

• With string instruments, INCREASING the tension
  (tightness) of the string will raise the pitch
• While DECREASING the tension will lower the pitch

Next, onto volume!
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Volume

• Volume is how LOUD or SOFT a sound is.
• Volume is measured in units called DECIBELS

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Volume
Softer volume
Louder volume
Notice that the frequency (how many waves per
second) does not change!
http//images.apple.com/uk/sound/images/sounddiagr
am20060509.gif
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Sound Review

• So lets review one more time
• What is pitch?

How loud or soft a sound is
How high or low a sound is
How fast or slow you play an instrument
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Correct!

• Next Question
• How would you increase volume?

Pluck a string harder
Pluck a string softer
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Nice try but lets review!
Back to Pitch vs. Volume
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Great Job!

• You finished the Sound Review! Click below to go
  onto the next study guide!

Sound Study Guide
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Nice Try but lets review!
Volume Review
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Videos from class

• Mythbusters Rubens Tube-visible sound wave
• Chladni Plate-Pitch patterns
• STOMP Broadway musical-Anything can make music!

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How do we hear sounds?

• Using our ears

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Our Ears!

• Our ears are made to collect sound vibrations and
  convert them into electric signals that are sent
  to the brain!

Vibrations
http//www.kids-ent.com/images/clinical
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Anatomy of the Ear
Take a close look. Do you remember the process of
hearing?
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How we hear sound
5. The cochlea fluid makes little hairs move
which create nerve signals that is understood as
sound in your brain!
1. Vibrations enter the outer ear
4. The inner ear bones causes the fluid in the
cochlea to vibrate
2. Vibrations cause the eardrum to vibrate
3. The vibrating eardrum makes the three middle
ear bones vibrate
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Kidshealth.org

• Read this article and watch this video on how
  your ear works. Did you find out anything new?
• Kidshealth.org
• Animation of how your ear works

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Review Question

• What process is NOT part of the hearing process?

Vibrations are collected by the outer ear
The Eardrum causes the middle ear bones to vibrate
The cochlea stops the sound before it reaches the
brain
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Correct!

• The cochlea does not stop the sound. It actually
  converts the sound to nerve signals which allow
  you to HEAR the sound!

Lets move on
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Nice try but lets review

Review now
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Ear Damage

• Can a loud sound hurt our ears? YES!
• Loud sounds can damage some inner parts of the
  ear. This can lead to temporary or permanent
  hearing loss! Protect your hearing by moving away
  from the sound or by wearing ear protection.

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Ear Damage

• Some people are born with hearing defects or get
  them from situations such as accidents. While
  there are a variety of reasons why somebody can
  lose their hearing, many defects are from a
  mechanical part of the ear that does not work
  properly (example, a burst eardrum cannot pass on
  vibrations!).

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Ear Damage

• There are ways to help people who have hearing
  defects.
• One example is a hearing aid which helps make
  sounds louder for the user. It is worn in or
  around the ear.

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Ear Damage

• For some people who cannot hear sounds, sign
  language is a type of communication that uses
  hand movements to indicate letters, words, and
  sentences.

www.asluniversity.com/.../fingerspelling.htm
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Review Question

• True or False?
• Loud music can cause hearing loss.

True
False
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Correct!

• Protect your hearing by moving yourself away from
  loud sounds or by using ear protectors!

Lets move on
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Nice try but lets review!
Review now
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Next Question

• Your ear is shaped to

Easily catch sound vibrations
Give you the ability to fly
Taste food
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Correct!

• You have completed the study guide! Nice job!

Yay! Click here to return to the main slide!
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