Education Technology


Flipping a Penny

Activity Overview

In this activity, students will explore two functions which are inverses of each other. They also explore their characteristics and understand how they reverse each other's operation.

Before the Activity

  • Connect the calculator to the CBR 2™
  • Install the TI Connect™ software to analyze data on the computer
  • See the attached PDF file for detailed instructions for this activity
  • Print pages 5 - 9 from the attached PDF file for your class
  • During the Activity

    Distribute the pages to your class.

    Follow the Activity procedures:

  • Run the Ranger program
  • Attach the plate to the spring and hang the spring from a ring stand
  • Position the CBR face up under the plate
  • Record the distance between the CBR and the plate
  • Add 5 pennies to the plate and measure the distance between the plate and the CBR
  • Repeat the above step until a total of 20 pennies have been added to the plate
  • Record the distance data and convert from meters to centimeters
  • Create a scatter plot using number of pennies versus distance data
  • Find the linear regression of the line and identify its slope and y-intercept
  • Plot the graph of the distance to the plate versus the number of pennies
  • Find the linear regression of the line, identify its slope and y-intercept
  • Compare the x- and y-intercept values for the two lines and determine the pattern between any function and its inverse
  • After the Activity

    Students will complete the Data Collection table and answer questions listed in it.

    Review student results:

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