What would jumping into a pool and feeling cold be called? Conduction, or convection?

This was another question from my son's workbook. It said:

Ever jumped into a pool on a warm day and still felt cold, even after measuring the
temperature of the water with a thermometer and finding that it is the same temperature as
the air? Would this be conduction, convection or radiation then?


Interesting question. When he asked me, I immediately thought of convection, as that is 'conduction' of fluids, right? But I wasn't too sure, and I asked some friends. Both conduction and convection came as answers.

Which one is it? Why?

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1 Answer

When first coming into contact with the water, it is conduction. The skin feels the water colder than air because water is a better conductor of heat than air. So the skin cools faster in water than in air.

For longer intervals convection will enhance the effect bringing cooler water next to the skin and removing the water already heated by the skin.

The difference will persist plotting water temperatures ( equal with air temperature) up to the temperature the skin raises the water when in contact with it. After that, the water is felt as warm.

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