Evaporation takes warmth with it
A wet hand feels cool as it dries. Why?
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Step 1 of 4
- A clay matka holds water inside.
- Water seeps through the clay to outside.
- That water evaporates from the damp surface.
- Evaporation pulls warmth away. The water stays cool.
The rule
Water that is drying takes warmth from your hand.
Turning liquid water into vapour needs warmth. The water takes that warmth from what it touches. So your hand loses warmth and feels cool.
Sweat is water from your skin. It cools the body the same way.
A matka is a clay pot. Clay has tiny holes. Water comes out slowly and evaporates. That takes warmth from the clay. So the water inside stays cool.