Education Technology

Lines, Models, CBR - Let's Tie Them Together (Electronic Format Only)

Published on 06/09/2008

Activity Overview

In this activity, students use a motion detector to collect "linear" motion data and examine the relationship between a physical action and a mathematical and/or graphic model of that action. The students will use the "eyeball" method to find the mathematical model.

Before the Activity

Install the Transformation Graphing application on the students' graphing calculators using one of these two methods:

  • TI Connect™,  a TI Connectivity Cable, and the Unit-to-Unit Link Cable
  • TI-Navigator™  "send to class" feature
  • Connect the CBR 2™ to the calculator using the Unit-to-Unit link cable
  • See the attached PDF file for detailed instructions for this activity
  • Print pages 11 - 16 from the attached PDF file for your class
  • During the Activity

    Distribute the pages to the class.

    Follow the Activity procedures:

  • Place the CBR on a table
  • Set up the Data Logger App to record one reading every 0.1 second for 6 seconds
  • Walk away from the CBR at a constant rate
  • Study the distance versus time graph
  • Set up an unconnected scatter plot of the data
  • Activate the Transformation Graphing application and use the slope-intercept equation to find the values of A and B that will form a line that models the data
  • Determine the slope, write the equation of the line which best fits the data
  • Understand the slope of the line represents the speed of the walker


  • In a second trial, students try to walk and duplicate the model graph
  • Use piecewise function to model the data
  • In a third trial, students try to walk and match the graph with a negative slope
  • In each trial, students identify how the direction and speed of motion affects the distance versus time plot
  • After the Activity

    Students will complete the Student Worksheet and answer questions listed on it.

    Review student results:

  • As a class, discuss questions that appeared to be more challenging
  • Re-teach concepts as necessary