Education Technology

Falling Down - Adventure 5

Published on 06/09/2008

Activity Overview

Students use the CBR 2™ to study how a change in mass affects the average speed of a falling object. They graph distance as a function of time, and interpret and analyze graphs representing motion.

Before the Activity

  • Connect CBR 2 to the calculator.
  • Launch the Ranger application
  • See the attached PDF file for detailed instructions for this activity
  • Print pages 35 - 36 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:

  • Hold the CBR 2 at eye level 0.5 meters directly above the concave side one coffee filter
  • Drop the filter and start recording distance - time data
  • Graph the data with time on the horizontal axis and distance from CBR 2 on the vertical axis
  • Understand what different sections in the graph represent
  • Repeat the experiment using 5 filters stacked together
  • Examine the Distance-Time plot and see that the stack of 5 coffee filters fell with the highest average speed.
  • Increase in mass caused the speed to increase


  • TI-Navigator activity:
  • Load the activity settings file CBRonFloor.act
  • Students mark points to illustrate what the plot of the coffee filters falling would have looked like if the CBR 2 had been placed on the floor and the filters released above it
  • Students also redraw for other conditions
  • After the Activity

    Students analyze the results and answer the questions in the worksheet

    Review student results:

  • As a class, discuss average speed, terminal velocity, and air resistance
  • Re-teach concepts as necessary