At the end of a chapter on Newton's Law of Cooling, Nagle and Saff's Fundamentals of Differential Equations and Boundary Value Problems poses the following problem:

Two friends sit down to talk and enjoy a cup of coffee. When the coffee is served, the impatient friend immediately adds a teaspoon of cream to his coffee. The relaxed friend waits 5 min before adding a teaspoon of cream (which has been kept at a constant temperature). The two now begin to drink their coffee. Who has the hotter coffee? Assume that the cream is cooler than the air and use Newton's law of cooling.

We will demonstrate a classroom experiment of this problem, explain how to import the data into Maple, and look at an interactive Maple demo created to complement the experiment. We will then discuss problems that arise with the experiment and with the model of Newton's law of cooling. We will summarize research done by a physicist analyzing cooling data and will discuss a better cooling model to use.

To conduct the experiment, we used a CBL unit, hand held technology that comes with temperature and other probes, which is becoming popular in high school and college classrooms. The interactive Maple demo, where students must answer questions in order to progress, can be found as Demo 4 on http://www.cs.appstate.edu/~sjg/class/3130/maple/maple.html