Science & TechFact

A kettle is loudest just before it goes quiet.

At the bottom the water reaches 100 degrees while the top is still at 70. Steam bubbles form there, rise into cooler water and collapse abruptly. Each collapse is a tiny bang; thousands per second add up to that roar. Only once all the water is boiling do the bubbles survive to the surface, and the kettle calms down.

Useful: When the kettle suddenly gets quieter, the water is almost done – get the tea ready.

Source: en.wikipedia.org

Akustik Alltag Physik

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