Why do small drops of hot water feel cold?

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Daniel

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Why do small drops of hot water feel cold?
« on: 26/11/2011 15:01:02 »
Daniel  asked the Naked Scientists:
   
Dear Chris,


Why do the first sprinkles of water that touch your skin when stepping into a hot shower seem cold... until you are fully in the shower stream?

Daniel Spain 
from Nashville, Tennessee USA

What do you think?
« Last Edit: 26/11/2011 15:01:02 by _system »

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Offline chris

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Why do small drops of hot water feel cold?
« Reply #1 on: 27/11/2011 10:28:32 »
Hi Daniel

I think the reason for this is that the smaller droplets have the lowest volumes and hence the least energy; consequently they cool more rapidly than the larger droplets in the body of the shower and so feel colder. They may also have arisen through the creation of "spray" when the warm shower droplets hit the sides / glass of the shower. As such the water that gave rise to them would have contacted a cooler surface, robbing the particles of their energy and cooling them.

Chris
I never forget a face, but in your case I'll make an exception - Groucho Marx

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Offline CliffordK

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Why do small drops of hot water feel cold?
« Reply #2 on: 29/11/2011 09:23:07 »
Yes, I was thinking of something similar.
It is not water that is directly hitting you, but droplets that are bouncing off the (colder) floor or sides of the shower.  Quite possibly there is a layer of cooler water on the floor or sides of the shower.  So, the water is actually hitting and scattering already cooler water.

Keep in mind that the water doesn't have to get much below body temperature to feel cool.