Question

Why does a cold glass sweat on a hot day?

Answer 1

Actually a cold glass doesn't sweat on a hot day. A cold glass when kept out on a hot day , its outer surface contains small water droplets.
This happens because the water vapour when comes in contact with the cold glass, gets condensed. This is the reason behind the formation of water droplets on the cold glass.
Hope it helps u.

Answer 2

as we know, the normal temperature of the surrounding environment is warmer than normal. Therefore, during that time, the temperature of the cold glass will always be less than its surroundings. And as we know, that heat is always transferred from a hot body to cold body.
So, the heat of the surroundings is absorbed by the cold glass, as well as the water vapour around the glass. And the vapour absorbs the heat and changes into water droplets, and it seems that the water is sweating!!!