Rotational Kinematics and Dynamics - rotkindyn1


A turntable (a flat disk) (mass = 5 kg, radius=0.3m) is rotating at a constant speed when your finger makes contact with the outer edge, as shown in the animation (position of a point on the outer edge of the turntable is shown in meters and time is shown in seconds). Friction between your finger and the turntable causes the turntable to stop. 


What is the average angular acceleration on the turntable caused by the frictional force? [6 rad/sec]


What is the angular "distance" (theta) that the tip of the arrow made as the wheel slowed to a stop? [~2.1 rev = ~13.2 rad]


What is the average frictional force applied to the wheel to stop it? [~4.5 N]


Physlet problem authored by Aaron Titus and modified by Mario Belloni. Further modified by Scott Schneider.