Education Technology

# Activities

• ##### Subject Area

• Math: Algebra II: Trigonometric Functions

9-12

60 Minutes

• ##### Device
• TI-73 Explorer™
• TI-83 Plus Family
• TI-84 Plus
• TI-84 Plus Silver Edition

TI Connect™

• ##### Accessories

CBL™/CBL 2™
Sensor - Motion Detector
TI Connectivity Cable
Vernier LabPro®

• ##### Other Materials
This is Activity 25 from the EXPLORATIONS Book:

The following materials are required for this activity :
• Pendulum bob
• Meter stick
• String
• Stopwatch

## Tic, Toc: Pendulum Motion

#### Activity Overview

In this activity, students' will use a motion detector to plot the position versus time graph for a swinging pendulum. They will determine the period of the motion and model the position data using a cosine function.

#### Before the Activity

• Connect the motion detector to the DIG/SONIC port of the CBL 2™ or DIG/SONIC 1 port of the Vernier LabPro®
• Connect the CBL 2 or LabPro to the calculator using the Unit-to-Unit cable
• See the attached PDF file for detailed instructions for this activity
• Print pages 247 - 252 from the attached PDF file for your class
• #### During the Activity

Distribute the pages to your class.

• Hang the pendulum bob from about 80 cm of string from a rigid support
• Position the motion detector about 1 m away from the bob, pointing at the bob
• Measure and record the distance from the bob to the motion detector; this distance must be at least 75 cm
• Pull back the bob not more than 20 cm before releasing it
• Measure the period of the pendulum and record it in the Data sheet
• Swing the bob away from the motion detector and observe the distance versus time graph
• Compare the data to the cosine model
• Determine the period of the pendulum
• #### After the Activity

Students' will analyze data and complete the Data Collection and Analysis Sheet. They will also answer questions listed in it.

Review student results

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