Session #2 Coffee Cup Experiment
(This activity will be conducted using the background information provided in session #1.)
Objectives:
Students
discover a relationship among type of material, thickness of material, shape of
material and heat transfer.
Students
learn how to quantify the relationship between rate of heat transfer and
temperature (heat loss model).
Activity:
Students will conduct an experiment using 4-5 different types of coffee
cups.
Step
1. Working in teams students will
hypothesize which cup will hold heat longest and why.
Step
2. Pour hot liquid into cup and
measure temperature immediately. Record
on data sheet as Temp1.
Step
3. Measure room temperature and
record on data sheet.
Step
4. Measure temperature in cup every
5 minutes for 30 minutes and record on data sheet as temp2, temp3,
etc.
Step
5. After temperatures have been
recorded, subtract room temperature from each trial and record on data sheet.
Step
6. Graph heat loss against
temperature difference to obtain linear relationship.
Step
7. Answer questions using graphical
data to compare heat loss rate of different coffee cups.
Example Quest. What influences heat transfer rate?
We
will present students (individually) with a set of heat loss graphs and they
will have to choose which one depicts a better design for a coffee cup.
This will tell us whether the student understands the heat loss model.
We
will ask the students to write down 5 ways or factors that could change heat
loss rate and how it would change it (increase or decrease the rate).
Explain why for each answer.