Two donut shaped magnets are stacked on top of eachother once the upper magnet is released it accelerates downward and stops 1 cm above the lower magnet how does the energy stored in the magnetic field change

Awind 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=0s? (c) what is the magnitude and direction of the total linear acceleration of the tip of the blades at t=0s?