Hot water can freeze faster than cold under certain conditions — a puzzle known as the Mpemba effect.

Physics

Science

Why it matters

The idea in context

Named after a Tanzanian student who noticed it while making ice cream, the effect is real but still debated. Evaporation, dissolved gases and convection currents may all play a part, and it does not happen every time.

Türkçe

Aynı kart, başka bir dilde.

Belirli koşullarda sıcak su, soğuk sudan daha hızlı donabilir — buna Mpemba etkisi denir.

Dondurma yaparken bunu fark eden Tanzanyalı bir öğrencinin adını taşıyan etki gerçektir; ama hâlâ tartışmalıdır. Buharlaşma, çözünmüş gazlar ve konveksiyon akımları rol oynayabilir; üstelik her seferinde de gerçekleşmez.

Source trail

Read beyond the card.

Batch 2026-07-05 (reviewed).

Background reading: Mpemba effectAttribution and context are revised when stronger evidence appears. Corrections are welcome through the editorial page.
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