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Sound Sound How does How does sound work? sound work?
SoundSound
How does How does sound work?sound work?
Sound: What is it?Sound: What is it?Sound is a disturbance that Sound is a disturbance that
travels through a medium travels through a medium as a longitudinal wave.as a longitudinal wave.
Interactions of sound waves:Interactions of sound waves:
Reflection: Sound waves reflect Reflection: Sound waves reflect when they strike an objectwhen they strike an object..
Interactions of sound waves:Interactions of sound waves:
Reflection: Sound waves reflect Reflection: Sound waves reflect when they strike an object.when they strike an object.You hear this as an echo.You hear this as an echo.
Interactions of sound waves:Interactions of sound waves:
Reflection: Sound waves reflect Reflection: Sound waves reflect when they strike an object.when they strike an object.You hear this as an echo.You hear this as an echo.
Diffraction: Sound waves “bend” Diffraction: Sound waves “bend” around corners or “squeeze” around corners or “squeeze” through a door.through a door.
Interactions of sound waves:Interactions of sound waves:
Reflection: Sound waves reflect when they strike Reflection: Sound waves reflect when they strike an object.an object.You hear this as an echo.You hear this as an echo.
Diffraction: Sound waves “bend” around corners Diffraction: Sound waves “bend” around corners or “squeeze” through a door.or “squeeze” through a door.
Interference: Sound waves may interact with Interference: Sound waves may interact with each other.each other.
Speed of sound waves:Speed of sound waves:
Depends on the elasticity, Depends on the elasticity, density, and temperature of the density, and temperature of the medium the sound is traveling medium the sound is traveling through.through.
Speed of sound waves:Speed of sound waves:
Depends on the elasticity, Depends on the elasticity, density, and temperature of the density, and temperature of the medium the sound is traveling medium the sound is traveling through.through.Elasticity: the ability of a material to Elasticity: the ability of a material to
bounce back after it is disturbed.bounce back after it is disturbed.
Speed of sound waves:Speed of sound waves:
Depends on the elasticity, Depends on the elasticity, density, and temperature of the density, and temperature of the medium the sound is traveling medium the sound is traveling through.through.Elasticity: the ability of a material to Elasticity: the ability of a material to
bounce back after it is disturbed.bounce back after it is disturbed.The more dense the medium the slower The more dense the medium the slower
sound travels through it.sound travels through it.
Speed of sound waves:Speed of sound waves:
Depends on the elasticity, density, Depends on the elasticity, density, and temperature of the medium the and temperature of the medium the sound is traveling through.sound is traveling through.Elasticity: the ability of a material to Elasticity: the ability of a material to
bounce back after it is disturbed.bounce back after it is disturbed.The more dense the medium the slower The more dense the medium the slower
sound travels through it.sound travels through it.The lower the temperature the slower The lower the temperature the slower
sound travels through a medium.sound travels through a medium.
Speed of sound waves:Speed of sound waves:
Air at room temp. = 343 m/sAir at room temp. = 343 m/s
Speed of sound waves:Speed of sound waves:
Air at room temp. = 343 m/sAir at room temp. = 343 m/sFresh water = 1,509 m/sFresh water = 1,509 m/s
Speed of sound waves:Speed of sound waves:
Air at room temp. = 343 m/sAir at room temp. = 343 m/sFresh water = 1,509 m/sFresh water = 1,509 m/sGlassGlass = 5,170 m/s = 5,170 m/s
Properties of sound:Properties of sound:
Loudness: Describes your Loudness: Describes your perception of the energy of the perception of the energy of the sound.sound.
Properties of sound:Properties of sound:
Loudness: Describes your Loudness: Describes your perception of the energy of the perception of the energy of the sound. sound. Depends on distance from the source Depends on distance from the source
and energy used to make the sound.and energy used to make the sound.
Properties of sound:Properties of sound:
Loudness: Describes your Loudness: Describes your perception of the energy of the perception of the energy of the sound.sound. Depends on distance from the source Depends on distance from the source
and energy used to make the sound.and energy used to make the sound.Measured in decibels (dB).Measured in decibels (dB).
Properties of sound:Properties of sound:
Loudness: Describes your perception Loudness: Describes your perception of the energy of the sound.of the energy of the sound. Depends on distance from the source Depends on distance from the source
and energy used to make the sound.and energy used to make the sound.Measured in decibels (dB).Measured in decibels (dB).
Intensity: The amount of energy a Intensity: The amount of energy a sound wave carries through an area sound wave carries through an area each second.each second.
PitchPitchA measure of A measure of how high or low a how high or low a
sound is.sound is.
PitchPitchA measure of A measure of how high or low a how high or low a
sound is.sound is.Pitch Pitch depends on the frequencydepends on the frequency of a of a
sound wavesound wave
PitchPitchA measure of A measure of how high or low a how high or low a
sound a is.sound a is.Pitch Pitch depends on the frequencydepends on the frequency of a of a
sound wavesound wave
PitchPitchA measure of A measure of how high or low a how high or low a
sound a is.sound a is.Pitch Pitch depends on the frequencydepends on the frequency of a of a
sound wavesound wave
- Low pitch
- Low frequency
- Longer wavelength
- High pitch
- High frequency
- Shorter wavelength
SonarSonar
SonarSonar- An instrument that uses An instrument that uses reflected sound reflected sound
waveswaves to find underwater objects to find underwater objects
SonarSonar- An instrument that uses An instrument that uses reflected sound reflected sound
waveswaves to find underwater objects to find underwater objects- For example,For example,
SonarSonar- An instrument that uses An instrument that uses reflected sound reflected sound
waveswaves to find underwater objects to find underwater objects- For example,For example,
SonarSonar- An instrument that uses An instrument that uses reflected sound reflected sound
waveswaves to find underwater objects to find underwater objects- For example,For example,
Animals use sonar or echo location to find their prey; these sounds have such a high pitch or frequency that the human ear cannot hear
SonarSonar- An instrument that uses An instrument that uses reflected sound reflected sound
waveswaves to find underwater objects to find underwater objects- For example,For example,
Animals use sonar or echo location to find their prey; these sounds have such a high pitch or frequency that the human ear cannot hear
SonarSonar- An instrument that uses An instrument that uses reflected sound reflected sound
waveswaves to find underwater objects to find underwater objects- For example,For example,
Humans use sonar to locate or
map objects
Animals use sonar or echo location to find their prey; these sounds have such a high pitch or frequency that the human ear cannot hear
Doppler Effect:Doppler Effect:
Definition: The change in frequency Definition: The change in frequency of a wave as its source moves in of a wave as its source moves in relation to an observerrelation to an observer..
Doppler Effect:Doppler Effect:
Definition: The change in frequency Definition: The change in frequency of a wave as its source moves in of a wave as its source moves in relation to an observer.relation to an observer.
Lower pitchHigher pitch
Blue Man Group Challenge!Blue Man Group Challenge!
Blue Man GroupBlue Man GroupYou’re HIRED!You’re HIRED!So what am I supposed to do exactly?So what am I supposed to do exactly?
Can I use or make an instrument Can I use or make an instrument that already exists?that already exists?
No way! You could, if you really wanted No way! You could, if you really wanted to…but wouldn’t you rather challenge to…but wouldn’t you rather challenge yourself to invent something never seen yourself to invent something never seen before? C’mon, I know you can do it! before? C’mon, I know you can do it! Besides, building a piano is really Besides, building a piano is really complicated. And putting a piece of string complicated. And putting a piece of string on top of a piano isn’t really on top of a piano isn’t really groundbreaking, either.groundbreaking, either.
Let’s look at some examples!Let’s look at some examples!
Let’s look at some examples!Let’s look at some examples!AwesomeAwesomeNot AwesomeNot Awesome
Shoe box with rubber bands attached Shoe box with rubber bands attached Oatmeal box with beads in it or paper on top Oatmeal box with beads in it or paper on top to create a drumto create a drum
Tambourines made from paper platesTambourines made from paper platesBongos made from tubs and paperBongos made from tubs and paper
