Serway & Jewett — Rotation of a Rigid Object about a Fixed Axis: Problem 44

As a gasoline engine operates, a flywheel turning with the crankshaft stores energy after each fuel explosion, providing the energy required to compress the next charge of fuel and air. For the engine of a certain lawn tractor, suppose a flywheel must be no more than 18.0 cm in diameter. Its thickness, measured along its axis of rotation, must be no larger than 8.00 cm. The flywheel must release energy 60.0 J when its angular speed drops from 800 rev/min to 600 rev/min. Design a sturdy steel (density \(7.85 \times 10^3\text{ kg/m}^3\)) flywheel to meet these requirements with the smallest mass you can reasonably attain. Specify the shape and mass of the flywheel.