Activity Overview
Students use a light sensor to analyze the effect of storm water run-off on the turbidity of local water. They interpret and analyze scatter plots and understand exponential relationship.
Before the Activity
Connect CBL 2™ to the calculator.
Plug light sensor into channel 1 of the CBL 2
Launch the DataMate program
See the attached PDF file for detailed instructions for this activity
Print pages 52 - 53 from the attached PDF file for your class
Transfer files to student calculators using TI-Navigator™ "send to class" feature
During the Activity
Distribute the pages to your class.
Follow the Adventure procedures:
Collect Data:
Align the flashlight, container of water, and the CBL 2 light sensor so that the light passes through the container of water directly into the light meter
Put 10 g of dirt in the water and stir
Note the amount of light transmitted to the light meter
Repeat the steps until 50 g of dirt have been added to the water
Record the light reading for each test
Graph the data as a scatter plot
Trace the points on the plot and explore graphs of exponential functions
Understand how water clarity decreases the most with the initial-run off
After the Activity
Students analyze the results and answer the questions in the worksheet
Review student results:
As a class, discuss questions that appeared to be more challenging
Re-teach concepts as necessary