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StillnessReflection

A kettle is usually loudest on its way to the boil, then quietens just before it clicks off. It's easy to miss when you're already reaching for the mug. Next time, stay where you are and listen for it.

Original reflection

Mind

The story behind the card

The pattern has a physical cause. As the water heats, bubbles of steam form on the hot element at the bottom and collapse suddenly when they rise into the cooler water above; those tiny collapses make the noise. Once all the water is close to boiling, the bubbles survive all the way to the surface, so the sound softens and settles shortly before the kettle clicks off.

Türkçe oku
Su ısıtıcısı en çok kaynamaya yaklaşırken ses çıkarır; kapanmadan hemen önce sesi azalır. Sen çoktan kupaya uzanmışken bunu kaçırmak kolaydır. Bir dahaki sefere olduğun yerde kal ve sesi dinle.

Bunun fiziksel bir nedeni var. Su ısınırken dipteki sıcak rezistansta buhar kabarcıkları oluşur; bunlar yukarıdaki daha soğuk suya yükselince aniden söner. Sesi çıkaran, bu küçük çöküşlerdir. Suyun tamamı kaynama noktasına yaklaşınca kabarcıklar yüzeye kadar sönmeden çıkar; bu yüzden ses, ısıtıcı kapanmadan kısa bir süre önce yumuşar ve durulur.

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