Activity Overview
In this activity, students' will use a pair of motion detectors to record the cartesian coordinates of a rod moving in a star-shaped pattern and calculate the distances moved between the vertices of the star. They also compare these calculated distances with direct measurements on the star pattern.
Before the Activity
Connect motion detectors to the DIG/SONIC ports of the CBL 2™ unit or the DIG/SONIC 1 and DIG/SONIC 2 ports of the Vernier LabPro® unit
Connect the CBL 2 or LabPro to the calculator using the Unit-to-Unit cable
Make a note of which detector will collect x-coordinates and which one will gather y-coordinates
See the attached PDF file for detailed instructions for this activity
Print pages 133 - 141 from the attached PDF file for your class
During the Activity
Distribute the pages to your class.
Follow the Activity procedures:
Position the star figure sheet and the motion detectors on the table
Move the rod along the star shaped pattern and collect data
Study the distance versus time graph and record the distance between the y-detector and the first vertex of the star shape
Trace the graph to display the coordinates of the vertices and record them in the Data table
Measure the length of each segment on the star pattern with a meter stick and record the values in the Data sheet
Compare the segment lengths calculated using the distance formula with those determined by direct measurement
After the Activity
Students' will complete the Data Collection and Analysis Sheet and answer the questions listed in it.
Review student results:
As a class, discuss questions that appeared to be more challenging
Re-teach concepts as necessary