With the aid of a string, a gyroscope is accelerated from rest to 16 rad/s in 0.40 s. what is its angular acceleration in rad/s2

Angular acceleration = (change in angular speed) / (time for the change)

Change in angular speed = (ending speed) minus (starting speed)

Change in angular speed = (16 rad/s) - (zero) = 16 rad/s.

Angular acceleration = (16 rad/s) / (0.4 s)

(Average) angular acceleration = 40 rad/s²