The Rolling Soda Bottle Experiment
You will need the following equipment:
· A long table
· One or two thick, hardcover books of the same thickness
· A 2 liter soda bottle filled with water
· A CBR2 motion sensor
· TI-Nspire CAS handheld with link cable for the CBR2
1. Set up the experiment as Follows: Prop up one end of the table slightly using the book(s). Position the motion sensor at the high end of the table (on its side) and aim it toward the low end.
2. Practice rolling the soda bottle up the table (from the low end) directly towards the sensor. The soda bottle should roll up the table, stop about 1 foot from the sensor, and then roll back down.
3. ***Turn on your TI-Nspire and open a New Document with a NOTES page.***
4. Connect the TI-Nspire calculator to the CBR2 with the link cable.
a. Choose Data & Statistics for the page type for the Data Collector.
5. When you are ready to collect data, press enter and gently roll the soda bottle up the table. Catch the soda bottle as it falls off the table. The sensor should stop collecting data after 5 seconds
6. If you did the experiment correctly, you should see a parabolic pattern in the graph. If you need to repeat the experiment, click the play button again and choose Discard when you are ready to roll to rewrite the data. When you have a good set of data (parabolic) end data collection as follows:
a. Tab over to the X-box on the data collector to close it.
b. Disconnect the CBR2 cable from your TI-Nspire.
7. The data collected by the sensor will have the form (dc01.time, dc01.dist1). Insert a new Graphs & Geometry page (should be page 1.3).
a. Change the Graph Type to Scatterplot (Menu->3: Graph Type->4: Scatter Plot)
b. For the x-variable choose dc01.time. For the y-variable choose dc01.dist1. Press enter.
8. Change the Window Settings (Menu->4: Window->1: Window Settings) to the following: XMIN: -1, XMAX: 6, YMIN: -0.5, YMAX: 2 (or lower, depending on the length of your table).
9. Change Graph Type to Function (Menu->3: Graph Type->1: Function).
10. Based on the data, the shape of the scatterplot and the situation, enter a reasonable approximation of a quadratic function IN VERTEX FORM to fit this data. You can then adjust the function graph to better-fit your data.
11. Record your best fit quadratic function and think about an explanation for why this function models the physical situation.
Adapted from Exploring Algebra 1 with TI-nSpire, Key Curriculum Press®, p. 111