Education Technology

Stretching a Penny

Activity Overview

In this activity, students investigate how a spring stretches when different weights pull on it. They relate the stretch of the spring directly to the weight and vice-versa.

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 1 - 4 from the attached PDF file for your class
  • During the Activity

    Distribute the pages 1 - 4 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 calculate the amount of stretch per penny
  • Add a handful of pennies to the plate, measure the distance, and predict the number of pennies
  • Count the pennies and compare with the predicted value
  • For a given number of pennies predict the stretch
  • Determine the proportionality constant for this variation
  • 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