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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:.
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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/s • Fresh water = 1,509 m/s
Speed of sound waves: • Air at room temp. = 343 m/s • Fresh water = 1,509 m/s • Glass = 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.
Pitch • A measure of how high or low a sound is.
Pitch • A measure of how high or low a sound is. • Pitch depends on the frequency of a sound wave
Pitch • A measure of how high or low a sound a is. • Pitch depends on the frequency of a sound wave
Pitch • A 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 • 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 pitch Higher pitch
Blue Man Group Challenge! • Blue Man Group • You’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! • Awesome • Not 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 plates • Bongos made from tubs and paper