PhysicsLAB Lab
Video LAB: Circular Motion

This lab is based on the video entitled Motion in a Circle from the Direct Measurement Video Project hosted at Science Education Research Center at Carleton College (SERC). The copyright for these videos belongs to School District 197 in Mendota Heights, Minnesota. The project is partially funced by a Science Foundtation Grant #1245268 awarded in September 2013.

The following lab implementation was designed for use in my Honors Physics I class and only represents one method of analyzing the data provided in the video. Notice at the bottom of the opening screen that there is a drop down listing of different radii. You will be viewing a total of nine (9) clips and recording the radius of the 500-gram hooked mass' center of mass, the scale reading, frame rate, and the frame numbers to complete five complete revolutions. Notice that there is a second drop down listing to change to frame rate. I would recommend using 240 frames/second. Before collecting data, play the video of radius#1 several times to become familiar with the scenario of the experiment.
 
At what frame rate did you play the videos while collecting your data? 


trial
radius
(m)
scale reading
(N)
starting
frame#
ending
frame# (5 rev)
average period
(sec)
average speed
(m/sec)
centripetal acc
(m/sec2)
radius #1
radius #2
radius #3
radius #4
radius #5
radius #6
radius #7
radius #8
radius #9
 
 
Before continuing with forward with your conclusions, you should have discovered that all nine (9) radii had the same period of revolution. If this is not true, go back and repeat any necessary trials. Once your data has been updated, continue on with the conclusions.  
 
Conclusions
 
Now you need to launch EXCEL and save your file in the physics Z:\drive as VideoCircularMotion_LastnameLastnameLastname.xls. You are now going to graph the data for the scale reading in newtons on the y-axis vs the centripetal acceleration in m/sec2 on the x-axis. After all of your data has been entered into EXCEL, create a scatter plot and add its trendline. Make sure to display the equation of the line and the value of R2.
 
Type in the names of the group members on the EXCEL file so that they will be displayed on the printout. Print a copy for each team member as well as one for your teacher. Please use print preview to make sure that your printout will only be one page. 
 
What is the name of your group's file that was saved on the physics z:\drive?
 

What was the common numerical value for the average period shared by all of the video trials? 

What information about the hooked mass' circular motion did the scale reading provide in each video?
 

Did the scale reading remain constant during each video? Use your physics knowledge to support you answer.
 

What was the R2 value for your graph? 

What was the value of your graph's slope? 

What physical quantity does the slope of your line represent in each of the experimental trials that you viewed while collecting data?
 

What was your group's percent error for the lab? 





Direct Measurement Video Project
Peter Bohacek
Copyright © 2013-2017
All rights reserved.
Used with permission.
PhysicsLAB
Lab Implementation
Copyright © 2014-2017
Catharine H. Colwell
All rights reserved.
Application Programmer
    Mark Acton