Education Technology

Activities

• Subject Area

• Math: Algebra I: Quadratic Functions

9-12

60 Minutes

• Software

TI InterActive!™

• Accessories

CBL™/CBL 2™
CBR™/CBR 2™
TI Connectivity Cable

• Other Materials
This is Activity 11 from the EXPLORATIONS Book:
TI InterActive!™ Data Collection and Analysis

Curve Ball

Activity Overview

In this activity, students collect data for a bouncing ball using a motion detector. They analyze the data and attempt to find a model for the height of the ball as a function of time.

Before the Activity

• Connect the computer to the CBL 2™ using the TI connectivity cable

• Connect CBR 2™ to the CH1 port of the CBL 2™ unit

• Open a new TI InterActive!™ document
• See the attached PDF file for detailed instructions for this activity
• Print pages 69 - 74 from the attached PDF file for your class
• During the Activity

Distribute the pages to the class.

• Hold the motion detector 5 or 6 feet above the ground
• Release the ball directly under the detector
• Collect distance versus time data and plot a graph
• Convert distance readings to height values
• Select the data of one bounce
• Observe the graph is in the form of a parabola
• Estimate and record the x- and y- coordinates of the vertex
• Note the theoretical model for an object in free fall is quadratic, and is modeled by the equation y = a(x - h)2 + k
• Enter coordinates of the vertex (h, k) and find and record the value y
• Use the model equation and adjust the value of a to find the best fit for the data and record the values of a, h, k, and y
• Use the TI-InterActive software to find a quadratic curve of best fit
• Find the regression equation y = ax2 + bx + c and its variables
• Compare the model equation with the new regression equation and observe that the models are identical
• After the Activity

Students complete the analysis and answer questions.

Review student results:

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