Question

Does water remain cold in earthen pots because of thermal expansion

Answer 1

Now the water losing heat energy consequently looses temperature making it cooler than the atmospheric temperature. That is why water remains cool in an earthen pot. ... In an earthen pot, water gets evaporated quickly through the pores. Cooling is caused by evaporation.

Answer 2

Water looses its temperature through small pores present in the pot. Hence in an earthen pot (matka) become cool during summer.