Rajesh took two identical glasses containing the same amount of hot milk at the same temperature He kept one glass undisturbed .While the other one he continously stirred using a spoon .Then among them milk in which glass cools faster ? Why?

Explanation

The milk in glass which is stirred by a spoon cools first. When we stir using a spoon, it will increase the movement of molecules. The cold molecules on the surface will settle at the bottom and hot molecules from bottom reach the top. Thus, stirring increase the heat transfer rate by convection