Question

why does water become cold if we add some ice cube to it

Answer 1

This occurs due to heat exchange between the molecule of the hot and the cold liquid. When ice melts, it needs heat to melt. Thus it takes the latent heat of fusion from the surrounding water molecules resulting in the lowering of the average temperature of water.

Answer 2

it occurs due to the heat exchange between the molecules of the hot and the cold liquid . thus it takes the latent heat of fusion from the surrounding water when ice needs heat to melt