PASCO ME-9833 Physical Pendulum Set - Manual (Page 21)

Physical Pendulum Set Model No. ME-9833
21
®
2. Click ‘Start’ to begin recording data. After about 30 seconds, click ‘Stop’ to end
recording data. Data will appear in the graph of angular position versus time and also in
the graph of period versus time.
3. Repeat the process for two more trials.
Analysis
1. Determine the average period of oscillation, T, for the pendulum bar and record the value in
the Data Section.
2. Assume that the center of gravity is at the midpoint of the pendulum bar. Measure and
record the distance from the pivot point to the center of gravity, L
cg
.
3. Calculate and record the theoretical moment of inertia about the center of gravity, I
cg
.
4. Calculate and record the acceleration due to gravity, g, based on the length from the pivot
point to the center of gravity, L
cg
, mass, M, moment of inertia about the center of gravity,
I
cg
, and period, T.
5. Calculate and record the percent different between the measured value for g, acceleration
due to gravity, and the accepted value (9.8 m/s
2
).
Data Section
Length of pendulum bar, a: _________________ Width of pendulum bar, b: __________________
Mass of pendulum bar, M: _________________
Average period of oscillation, T: ________________
Distance from pivot to center of gravity, L
cg
: ________________
Calculated value for the moment of inertia about the center of gravity, I
cg
: _______________
Calculated value for acceleration due to gravity, g: __________________
Percent difference: ___________________
Questions
1. How does the calculated value for g based on the period compare to the accepted value for g,
9.8 m/s
2
?
2. Do your results confirm that the acceleration due to gravity, g, can be measured
accurately using a physical pendulum? Why or why not?