Physics Rotation?

1. Moment of inertia of disk = (1/2).(8.8).(6.4)^2 kg.m^2 = 180.2 kg.m^2
Torque applied to disk = 31.5.cos(35) x 6.4 Nm = 165.1 Nm
Hence, angular acceleration of disk = 165.1/180.2 rad/s^2 = 0.9162 rad/s^2

Angular displacement of disk = 5.6 x (2.pi) radians = 35.19 radians
Use the equation of motion: w^2 = (wo)^2 + 2.a.s
where w and (wo) are the final and initial angular velocities of the disk respectivrly; a is the angular acceleration; s is the angular displacement.

Hence, w^2 = 0^2 + 2 x 0.9162 x 35.19
w = 8.03 rad/s
Thus, tangential velocity at the rim = 8.03 x 6.4 m/s = 51.39 m/s
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2. Moment of inertia of the propeller = (1/12).(3.6).(2.2)^2 kg.m^2
= 1.452 kg.m^2
Hence, angular acceleration = 8.6/1.452 rad/s^2 = 5.923 rad/s^2