1. December 11, 2006 Matthew Vogel Matt Nichols Cold Hands? Which Hot Chocolate Cup is the best Hand Warmer?

2. Cold Hands?  Life is so much harder when your hands are cold.  There are plenty of hand warmers out there.  This project investigates the phenomenon of warming your hands while enjoying a national past-time — drinking hot chocolate. The picture to the left depicts how much of your hand is in need of warming when your hand “feels” cold Courtesy of www.heatbands.com/ Above pictures courtesy of Google Images “hand warmers”

3. The Best Hand Warmer?  Which cup acts as the best Hand Warmer?  Plastic Cup  Ceramic Mug  Styrofoam Cup Above pictures courtesy of Google Images “plastic cup, mug, Styrofoam cup”

4. The Project  This project is NOT interested in which cup is the best insulator.  This project investigates how different cups for your hot chocolate can allow you to effectively warm your HANDS and insides.  Specifically, this project investigates which cup keeps the outside temperature of the cup between 40 and 50 o Celsius

5. The Experiment  The test apparatus was set up to measure temperatures of the inside water every 30 seconds.  The test was repeated for all 3 different cups. Thermocouple designed to take temperature measurement from center of water Data acquisition system Watch allowed us to monitor results every 30 seconds Water brought to a boil

6. Data Analysis and Assumptions  Assumptions:  Cups are perfect cylinders  The water was moving inside the cup causing forced convection and thus the inside temperature of the cup was the temperature of the water. q” cond,k q” conv,h Wall of Cup T1T1 TsTs

7. Data Analysis

8. The Results-Water Temp

9. The Results-Surface Temp T p = 15 min T m = 17 min

10. So In the Future?  Remember a ceramic mug just doesn’t keep your hot chocolate warm it also keeps your Hands warm.  If it is a cold day outside and you are without a mug, grab a Plastic cup before a Styrofoam one to make for more pleasant drinking with Warm Hands. Courtesy of www.heatbands.com/