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Tufts OpenCourseware
Author: Fulcrum Institute Development Team

Why do things end up at room temperature?

GO! Temp Graphs

Scenario 1: Heating Coffee

Suppose that you have two identical pyrex cups of room temperature coffee. One cup contains 50 ml and the other contains 150 ml of coffee. You place them side by side on a heating plate for the same length of time.

Scenario 2: Coffee Cools

You have 2 identical pyrex cups, each containing 80 ml of coffee. The coffee in one is 50°C, the second is 80°C. You leave them side by side on the counter for an hour.