Re: Why does a jar with human hair and water evaporate faster than just the wat

Hi Patrick!

Probably because the area of the water's surface was increased because of the hair.

Water can only evaporate from its surface, right? The bigger the surface, the more opportunity for evaporation. Usually if the surface of the water is made larger, evaporation will be faster. If you put the same amount of water in a bowl and also in a large tray, the water in the tray will dry out first. Water on the floor dries quickly, while water in a narrow-necked bottle will take forever to evaporate.

Why would the hair make the water's surface larger? Because wet hair counts as water surface. The hair must stick up out of the water for this to work. Water creeps up along the hair, then evaporates. The jar full of wet hair might look the same as the other jars, but in reality, the surface area of the water on the hair is huge.