PASCO ME-9821 Centripetal Force Pendulum - Manual (Page 11)

Centripetal Force Pendulum Model No. ME-9821
10 ®
Questions
1) At what angular position does the centripetal force become zero?
(Hint: Look at your graph.) Is there a trend?
2) Did changing the radius alter the maximum centripetal force?
3) Can you predict the angle at which zero centripetal force occurs?
EXPERIMENT RESULTS:
EXPERIMENT 1 - SAMPLE DATA
a) Brass mass = 100 g (0.1 kg)
b) Length (r) from axis of rotation to mass = 18.5” (0.4699 m)
*Expected centripetal force at maximum angular velocity
Note: The pendulum rod’s length was measured as the distance from the
center point of the thumbscrew (attached to the Force Sensor) to the
center point on the mass. Measuring from the top point of the pendulum
gives erroneous data.
Trial
Number Angle of the
pendulum
(degrees) Maximum
Angular
Velocity (
)
Tangential
Speed (v) Expected
Centripetal
Force
(N)*
1 63.0 4.8 rad/s 2.3 m/s 1.1
2 90.4 6.0 rad/s 2.8 m/s 1.7
3 214.7 8.8 rad/s 4.1 m/s 3.6
Trial
Number Release
Angle
(Degrees) Measured
Centripetal
Force (N) Expected
Centripetal
Force (N)* Percent
(%)
Difference
1 63.0 1.1 1.1 0.0%
2 90.4 1.9 1.7 10.5%
3 214.7 3.7 3.6 2.7%
ω
* Expected centripetal force was calculated with the measured
maximum angular velocity.