Under certain conditions a body of hot liquid may cool faster and freeze before a body of colder
liquid, a phenomenon known as the Mpemba Effect. An initial difference in temperature of 3.2 °C
enabled warmer water to reach 0 °C in 14% less time than colder water. Convection currents in the
liquid generate a temperature gradient that causes more rapid heat loss by surface radiation and
evaporation than obtains for uniform temperature. This more rapid cooling enables the initially
warmer liquid to overtake the cooler liquid, reaching 0 °C earlier and freezing first. Liquid
cooling under natural convection follows a five-fourths power law (temperature of liquid ##IMG##
[http://ej.iop.org/images/0031-9120/51/2/025011/pedaa0af1ieqn001.gif] {$T$} , temperature of
surroundings ##IMG## [http://ej.iop.org/images/0031-9120/51/2/025011/pedaa0af1ieqn002.gif]
{${{T}_{a}}$} , cooling constant ##IMG## [http://ej.iop….] {$k$}