Watch: Have you ever seen water flow so evenly that it appears frozen?
Laminar flow, a phenomenon in fluid mechanics concerned with liquid that flows in parallel layers, allows for this fascinating effect.
When water flows so smoothly it looks solid. This effect is called Laminar flow. pic.twitter.com/XLDtlLF2PD
— Universal Curiosity (@UniverCurious) December 5, 2019
While the video above may look like an optical illusion, it is actually reducible to the very basics of physics.
Aptly named after laminae (thin layers or plates), a laminar flow occurs when the stream or channel of flow is relatively small. The fluid also has to be moving slowly, and its viscosity must be relatively high.
The viscosity of water increases with pressure, which is probably the case here. The flow of oil through a thin tube or blood flow through capillaries is also laminar in nature.
Below is a video of another fascinating effect achieved by high viscosity laminar flow in a liquid.
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