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Experiment:  The motion of a pendulum can be modeled by motion around a circle, with one complete cycle around the circle corresponding to one complete cycle of the pendulum from extreme point back through equilibrium to the opposite extreme point, back through equilibrium and returning to the original point.

Take a pendulum with length between 10 cm and 40 cm, as assigned, and estimate how the number of radians per second necessary to achieve this model.

Set up the SHM simulation with this number of radians per second, and compare the motion of your pendulum with the simulation.  Adjust the angular frequency of the simulation until you get a the best possible match of frequencies.

I necessary adjust the radius of the circle in the simulation, then oscillate the pendulum directly in front of the screen so that the pendulum stays exactly with the vertical line throughout the simulation.

What is the length of your pendulum, and what angular frequency is necessary so that the simulation precisely matches the motion of the pendulum?

For a pendulum we recall that

• Fnet = - kx with
• k = m g / L.

The angular frequency of an object subject to net force Fnet = - k x is

• omega = sqrt(k / m).

So what is L for your pendulum?

What was the velocity with which the pearl pendulum struck the meter stick?

What was the angular momentum of the pearl before collision, relative to the axis of rotation?

What was the angular momentum of the meter stick immediately after collision?

What was the angular momentum of the pearl immediately after collision?

Was angular momentum conserved?