It has been observed by many people that hot water appears to freeze faster than cold water. Many videos of citizen scientists testing this hypothesis can be found on YouTube, especially in areas experiencing colder than usual temperatures.
Although scientists have also observed this phenomenon and named it the Mpemba effect, until recently, its existence had not been adequately verified and the precise mechanism that causes this observation had remained unclear. Recently, researchers from Simon Fraser University in Canada published important observations of tiny glass beads in a simulation of cooling water.
While the thought of a hot liquid turning to ice more quickly than a cold liquid may seem counterintuitive, the researchers observed that beads (representing individual water molecules) could be more quickly rearranged into a configuration that matched a lower temperature when the beads themselves were hot. Thus, the apparently counterintuitive observation that has been replicated in many YouTube videos has a solid explanation in physics.
YouTube may often be seen as a site best suited to wasting time on mindless entertainment; however, scientists can use it to find inspiration for research that can help us to better understand our world.
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