The rotational speed of a shaft powered by an electric motor is controlled such that it cannot exceed 450 rev/min. A switching mechanism disconnects power once the shaft hits 450 rev/min. Suppose the shaft has a mass of 36.0 kg and a diameter of 420 mm and power is disconnected at t = 0. The shaft slows down as it delivers power to a load. If it makes 140 revolutions before power is reconnected at t = 23.0 s, what is the rotational speed in RPM at the moment the power is reconnected?