Sound and Hearing

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Sound and Hearing
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Speed of sound
The speed of sound in air is around 330 m/s.
What happens when sound travels through different
materials?
Speed of sound (in m/s)
Material
Conclusion the denser the material, the faster
sound travels through it
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Making Sounds
A sound is made when an object or material
VIBRATES.
Take, for example, a guitar.
To make a sound with a guitar a string has to
vibrate. We can raise the pitch of the sound a
guitar makes by doing three things 1) _________
the length of the string 2) _________ the
string 3) Using a _________ string
We can make the sound louder by ________ the
string harder
Words tightening, thinner, increasing, plucking
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Using an oscilloscope
1) Quiet sound, low frequency
2) Quiet sound, high frequency
3) Loud sound, low frequency
4) Loud sound, high frequency
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How sound travels
As we know, sound waves are formed when something
vibrates. But how does the sound reach our ears?
Air molecules
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How does the ear work?