Coffee Cooling (RBD3411)

As any coffee drinker would notice, a cup of hot java eventually gets "cold." In more scientific terms, the cup of coffee has attained thermal equilibrium with the surrounding temperature. But how long does it take for coffee to cool down?

This is a classic example of Newton’s Law of Cooling which states that the rate of temperature change of an object is proportional to the temperature difference between the object and its surroundings. In other words, as our cup of coffee nears room temperature, its change in temperature slows down. If we are to plot our coffee temperature with respect to time, the resulting plot will not be a straight line.

So how do we create a computer model of the coffee’s change in temperature? This article will step by step, lead you through that fascinating problem. And amazingly, in the end, you will understand what was going on. Never look at a cup of coffee the same way again!