Analysis – PASCO ME-8092 Force Distribution Apparatus User Manual

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F o r c e D i s t r ib u t i o n A p p a r a t u s

P ro c e d ur e

Place the ball at the end of the beam closest to the motion sensor. Click

Allow the ball to roll along the beam away from the motion sensor. Catch the ball
as it rolls off the end.

Data recording will start when the ball is 0.2 m from the motion sensor.
Recording will stop when it reaches 1.1 m (just before the end of the track).

If necessary, adjust the angle and position of the motion sensor and repeat data
collection in order to obtain a smooth, continuous position versus time graph.

Analysis

Because you zeroed the force sensors with the beam mounted on them, the weight of
the beam is not part of the recorded force data. For this analysis, treat the beam as
though it were massless.

Observe the force versus position graph for one of the force sensors. Why is the
force positive in one part of the graph and negative in the other part? When the
force changes from positive to negative (or from negative to positive), where is
the ball?

Observe the graph showing the sum of measured forces (total force) versus ball
position.

How does the total force vary as the ball rolls along the beam? (Consider any
variation as a percentage of the total force).

Compare the average value of the total force to the weight of the ball.

List all of the objects that exert force on the beam. For any position of the
ball, what is the net force on the beam? (Remember to treat the beam as
massless.)

Observe the table showing the position of the ball measured by the motion sensor
and the forces measured by both force sensors. Using only this data, determine
the distance from the motion sensor to each force sensor. (Hint: when the ball is
directly over one force sensor, the reading from the other force sensor is zero.)

Choose a point in the data table where the ball was somewhere between the force
sensors.

What is the position of the ball and the readings of both force sensors at that
point?

The formula for the torque,

, exerted by an object is

= rF, where r is the

lever arm (or distance from the motion sensor to the object) and F is the
force exerted by the object. Since all distances are measured from the motion
sensor, this formula gives the torque about the position of the motion sensor.

Calculate the torque exerted on the beam by each object that interacts with it.
Don't forget to include the torque applied by the ball. Why do you not need
to consider the weight of the beam?

Calculate the total torque that tends to rotate the beam clockwise and the
total torque that tends to rotate the beam counter-clockwise. How do they
compare? What is the net torque on the beam?

To adjust the delayed

start and automatic stop
parameters, click the
Setup button in
DataStudio’s main tool
bar; the Experiment
Setup window will open.
Click the Sampling
Options button.