Newton's Law of Cooling 








Here are some questions that I have made up so you can have additional practice with "Newton's Law of Cooling" type problems. It is assumed you have already leaned the basics about these kinds of differential equations and are just looking for extra practice. If you are not familiar with this type of differential equation, please refer to the tutorial on differential equations. 
Stage 1: Not many words. 1. If y'=2(25y) and y(0)=75, find the particular solution.
2. If y'=153y and y'(1)=12, what is y(1)?
3. If y'=4y/2 and y'(0)=8, what is y(0)? 
Stage 2: Word problems. 4. After spending many hours study for your math class you decide to reward yourself with a case of Stiffler Soda. Unfortunately I.V. Market only had warm case left, the physics students got there first and got all of the cold ones. You buy several bags of ice and decide to chill it at home. When you get home the temperature of the soda is 76 degrees F and you proceed to pack it in ice. After ten minutes the temperature has cooled to 70 degrees F. If Stiffler Soda is best served at 60 degrees F or cooler, how much longer must you wait to enjoy your Sriffler Soda? 
By
Lee DeAnda
Ó 2003 All rights reserved.