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Exploration 11.4: Moment of Inertia and Angular Momentum
Please wait for the animation to completely load.
A 1-kg red mass is incident on an identical black mass that is attached to a massless rigid string so that it can rotate around the origin as shown (position is shown in meters and time is shown in seconds). At t = 2.6 s the red mass undergoes a completely elastic collision with the black mass. Restart.
Watch the animation. You may vary the radius of the pendulum between 2 and 10 m. Answer the first three questions before clicking the "see other variables" check box.
- As you reduce the length of the pendulum, does the angular speed of the pendulum increase or decrease?
- From what you know about conservation laws, state whether you think linear momentum, angular momentum, and kinetic energy are conserved during the animation. Why?
- Set R = 5 m. Calculate the linear momentum, angular momentum (about the origin), and kinetic energy of the system at t = 1, 2, 4, and 5 s.
You may now click the check box.
- If your answers differ from what you thought, explain why they differ.