An engine flywheel initially rotates counterclockwise at 5.03 rotations/s. Then, during 23.5 s, its rotation rate changes to 2.63 rotations/s clockwise. Find the flywheel's average angular acceleration (including its sign) in radians per second squared. Define counterclockwise rotation as positive.

the flywheel's average angular acceleration is -2.05 rad/s²

Explanation:

Note: counterclockwise is positive

         clockwise is negative

Given;

initial angular velocity, = 5.03 rev/s =

final angular velocity, = -2.63 rev/s =

duration of the flywheel rotation, Δt = 23.5 s

The average acceleration of the flywheel is calculated as;

Therefore, the flywheel's average angular acceleration is -2.05 rad/s²

i think its d if wrong im sorry