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.
Follow the Activity procedures:

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 = ax^{2} + 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