Explain how cold milk cools hot cocoa?

Cold milk cools hot cocoa through a process called heat transfer. Here's how it works:

* Hot cocoa has higher energy: The hot cocoa molecules are moving faster and have more energy than the cold milk molecules.

* Collision and transfer: When the cold milk is added to the hot cocoa, the molecules collide. The hot cocoa molecules, with their higher energy, transfer some of that energy to the colder milk molecules.

* Temperature equalizes: As the milk molecules gain energy, they start moving faster, which means the milk warms up. At the same time, the hot cocoa molecules lose energy and slow down, causing the cocoa to cool down.

* Equilibrium: This transfer of energy continues until the hot cocoa and milk reach a state of thermal equilibrium, where they are both at the same temperature.

Essentially, the cold milk acts as a heat sink, absorbing the excess heat from the hot cocoa until the temperature difference between the two is eliminated.