<p> Torque and Rotational Motion </p><p>You will be given apparatus like that diagramed below to be used in this experiment.</p><p>Your task is to write and carry out a procedure to test the relationship between the torque exerted on the apparatus and the change in angular velocity, , about its axis. In your report you should provide data, a graph of the data and the equation for the best fit for the graph. Discuss the relationship you have found.</p><p>The apparatus design is based on ideas that appeared in two articles in The Physics Teacher: Measure Centripetal Force for Under $3 by Joe Bunn and Jay Smith, TPT VOL 32, page 380 (Sept 1994) and An Inexpensive Moment of Inertia Experiment by Peter E. Banks, TPT Vol 43, page 389 (Sept 2005). </p><p>In the second article Peter stated that the error was a bit large. I made two changes in the apparatus to reduce this error. 1) A marble was added under the top cap to reduce the torque of friction, and more importantly 2) The a “reducer” was used to increase the radius to double that of the pipe. This is important for the follow up experiment Rotation II in which the rotational inertia, I, is to be determined. Because the radius is used twice it ends up appearing as r2 in the calculations. The result is that the smallest error in radius can greatly increase the error in the rotational inertia, I. For that experiment larger masses, ~500g, seem to produce better results. – Joe Stieve</p>