Engineers at the University of Texas at Austin are developing an Advanced Locomotive Propulsion System that uses a gas turbine and perhaps the larghigh-speed flywheel in the world in terms of the energy it can store. The flywheel can store 4.8 * 10 ⁸ j of energy when operating at its maximum rotational speed of 15,000 rpm. At that rate, the perimeter of the rotor moves at approximately 1,000 m/s.

-Determine the radius of the flywheel.

-Determine the rotational inertia of the flywheel.