cold hands? which hot chocolate cup is the best hand warmer?
DESCRIPTION
Cold Hands? Which Hot Chocolate Cup is the best Hand Warmer?. December 11, 2006 Matthew Vogel Matt Nichols. Cold Hands?. The picture to the left depicts how much of your hand is in need of warming when your hand “feels” cold. Life is so much harder when your hands are cold. - PowerPoint PPT PresentationTRANSCRIPT
December 11, 2006
Matthew Vogel
Matt Nichols
Cold Hands?Cold Hands?Which Hot Chocolate Cup is the Which Hot Chocolate Cup is the
best Hand Warmer?best Hand Warmer?
Cold Hands?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”
The Best Hand The Best Hand Warmer?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”
The ProjectThe 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 50o Celsius
The ExperimentThe 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
Data Analysis and Data Analysis and AssumptionsAssumptions
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.
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Wall of CupT1 Ts
Data AnalysisData Analysis
The Results-Water The Results-Water TempTemp
Rate of Water Temperature Change
35
40
45
50
55
60
65
0 5 10 15 20 25 30 35 40
Time (min)
Tem
per
atu
re (
oC
)
Plastic Cup
Styrofoam Cup
Ceramic Mug
The Results-Surface TempThe Results-Surface Temp
Surface Temperature
0
10
20
30
40
50
60
70
0 5 10 15 20 25 30 35
Time (m)
Tem
pera
ture
(oC
)
Plastic Cup
Styrofoam Cup
Mug (Ceramic)
Tp= 15 min
Tm= 17 min
So In the Future?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/