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(GIST OF SCIENCE REPORTER) Mpemba Effect

(FEBRUARY-2024)

Mpemba effect captivates scientists due to its complex interplay of physical mechanisms.

Fast-freezing of hot water is known as the Mpemba effect.
This effect is named after a Tanzanian schoolboy called Erasto Mpemba. He brought attention to this counterintuitive phenomenon in 1969.

After numerous experiments to determine the causes of this confusing phenomenon, findings remain inconclusive.

Microbubbles remaining suspended in heated water from boiling are identified as one contributing factor. These bubbles facilitate convection, expediting heat transfer as the water gradually cools.
Additionally, warmer water, which evaporates more readily, further aids in heat removal as evaporation inherently absorbs heat.
The effectiveness of both convection and heat transfer is heightened in warmer water due to its lower density.
Another potential influence may be the presence of frost in colder water, which acts as an insulator, potentially impeding heat loss.