Exploring Whistles

How do whistles work?

Typically whistles involve air streams that flutter against each other.

Take the typical whistle where the air rushes straight in and curls around. It has to break through an earlier part of of the air stream to get out the top. This creates an unstable situation, with the air streams fighting for dominance.

They alternate thousands of times per second, creating high-pitched sound. If you could see the air bursts, you would actually see thousands of tiny vortices (like tornados) dancing around. The illustration in this link shows vortices being formed in a organ pipe.

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