Instruments
Of course no concert is complete with
instruments. We are all grateful for the wonderful noise
they create, but not many people think about the physics
behind whatever instrument is being played. All instruments
create a sound wave that then travels through the air to
reach the listeners ear.
How Guitars Work
Instruments work because of standing
waves created by constructive interference between waves
traveling along a string or tube. On a guitar each string
has a different frequency, because they change in
mass/length. To create a new frequency (or note) from a
string, the guitar player shortens the string, the frequency
is increased.
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