Relating Angular and Translational Quantities (Problem 49)

A wind turbine is rotating counterclockwise at 0.5 rev/s and slows to a stop in 10 s. Its blades are 20 m in length. (a) What is the angular acceleration of the turbine? (b) What is the centripetal acceleration of the tip of the blades at $t=0\text{s?}$ (c) What is the magnitude and direction of the total linear acceleration of the tip of the blade that lies along the positive x-axis at $t=0\text{s?}$ Select the answer to part (a).