When hot iron nail is kept in the cold water, the temperature of iron decreases, whereas temperature of water increases, Why?

When the temperature of an object increases, the average kinetic energy of its particles increases. When the average kinetic energy of its particles increases, the object's thermal energy increases. Therefore, the thermal energy of an object increases as its temperature increases.

Explanation:

the heat leaves the nail into the water

if they have a finite resultant

molecules are free to separate from each other and will take on the shape of the container. molecules move completely at random and high speeds. they vibrate in a fixed position and do not move around much. molecules expand to the edge of their container.