The goal of the problem is to calculate the angular acceleration of the rotor. The analysis for this is provided below. This result shows that, although both rotation components for the rotor are ...

This says that an angle-time plot should be a parabolic function. If I fit a quadratic equation to the data, the coefficient in front of the t 2 term should be 1/2 times the angular acceleration (α).

At t 2, the angular velocity is zero, with a non-zero (positive) angular acceleration. At that time, the direction of rotation for BC is changing from CW to CCW. In summary, you should never assume ...