I am sitting in my apartment with my windows open and a car drove by and as it did, the music got distorted the further away to got. I’ve noticed this too while walking to class and someone is blasting music in their car.
In: Physics
This is called the Doppler effect. The sound waves are closer together as the car drives towards you because the speakers are moving as they create the ripples in the air. This makes the pitch of the sound higher. As the car drives away, the waves are further apart than they would be if the car were not moving, so the pitch gets progressively lower.
Interestingly, the same thing happens to light waves when we observe really distant and fast moving objects, but instead of sounding higher or lower, the light looks more blue or red.
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