Activity Overview
In this activity, students use the CBL 2™ to collect temperature data as a sensor warms up in a cup of water. They find an appropriate mathematical model for the resulting data set.
Before the Activity
Connect the calculator to the CBL 2 unit using the link cables
Connect the temperature sensor into channel 1 of the CBL 2 unit and start the DataMate program
See the attached PDF file for detailed instructions for this activity
Print pages 41 - 47 from the attached PDF file for your class
During the Activity
Distribute the pages to the class.
Follow the Activity procedures:
Place the temperature sensor in a cup of hot water and collect temperature versus time data
Model the temperature data using a modified exponential function
y = a(1 - b^x) + c where x = time and y = temperature
Find c (the starting temperature), and y (the approach temperature)
Solve for the value of a
Use different values of b and find a value of b such that it gives a graph that best fits the data generated
Use the DataMatrix editor to perform an exponential regression
Verify if the values of a and b match those from the model
Plot the regression curve and compare it with the modeling curve to find how well the equation fits the data
After the Activity
Review student results:
As a class, discuss questions that appeared to be more challenging
Re-teach concepts as necessary