A car is designed to get its energy from a rotating flywheel with a radius of 1.90 m and a mass of 510.0 kg. Before a trip, the disk-shaped flywheel is attached to an electric motor, which brings the flywheel's rotational speed up to 1008.0 rev/min. (a) Find the kinetic energy stored in the flywheel. J (b) If the flywheel is to supply as much energy to the car as a 7457 W motor would, find the length of time the car can run before the flywheel has to be brought back up to speed again. s trying to solve this problem is killing me.. Any hints or tips?