Wireless Rotary Motion Sensor Experiment 3: Conservation of Angular Momen-
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013-15949A
3.
.In the data collection software, create an
experiment to measure the angular velocity (in
radians per second) versus time (in second)
of the disk before and after the ring is dropped
on top of it.
•
In PASCO Capstone, for example, drag the
Graph icon from the Displays palette to the
workbook. Select “Angular Velocity (rad/s)” for
the vertical axis, and “Time (s)” for the
horizontal axis.
Procedure
1.
Hold the thin ring just above the disk align-
ment guide that is on the top of the disk.
2.
Give the disk a spin with your hand and click
Record to begin recording data.
3.
After about 25 data points have been
recorded, drop the thin ring onto the spinning
disk. See Figure 3.1.
4.
Click Stop to end data recording after the disk
and ring have made a few rotations.
5.
In the Graph display, select the region of the data that represents when the ring was dropped onto the disk.
6.
In the Graph display, select the data analysis tool that shows the coordinates of any point in the plot of data
and move the cursor to the data point that is immediately before the collision. Record the Angular Velocity at
this point as the initial angular velocity in the Data Table.
7.
Move the cursor to the data point immediately after the collision. Record the Angular Velocity at this point as
the final angular velocity in the Data Table.
8.
Weigh the ring and disk and record their masses. Measure the inner and outer radii of the ring, and the radius
of the disk. Record these values in the Data Table.
Analysis
1.
Calculate the theoretical value for the final angular velocity and record this value in the Data Table.
2.
Calculate the percent difference between the experimental and theoretical values of the final angular velocity
and record it in the Data Table.
Figure 3.1: Setup for Dropping Ring onto Disk
Disk
WRMS with
3-step Pulley
Figure 3.1 Setup for Conservation of
Angular Momentum