Question: Newton Cooling. According to Newton's law of cooling, an object of higher temperature than its environment cools at a rate that is proportional to the difference in temperature.
(a) A thermometer reading 70°F, which has been inside a house for a long time, is taken outside. After one minute the thermometer reads 60°F; after two minutes it reads 53°F. What is the outside temperature?
(b) Suppose you are served a hot cup of coffee and a small pitcher of cream (which is cold). You want to drink the coffee only after it cools to your favorite temperature. If you wish to get the coffee to proper temperature as quickly as possible, should you add the cream immediately or should you wait awhile?