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