(adsbygoogle = window.adsbygoogle || []).push({}); A flywheel is a solid disk that rotates about an axis that is perpendicular to the disk and its center. Rotating flywheels provide a means for storing energy in the form of rotational kinetic energy and are being considered as a possible alternative to batteries in electric cars. The gasoline burned in a 387-mile trip in a typical midsize car produces about 1.4 x10^9 J of energy. How fast would a 16-kg flywheel with a radius of 0.22 m have to rotate in order to store this much energy? Give your answer in rev/min.

I know the kinetic energy of a flywheel is: http://content.answers.com/main/content/wp/en/math/1/4/8/148da762c81d0061d84cb36a21fb1e4e.png [Broken] but how do I use that information to calculate how fast the flywheel needs to rotate? Thanks

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# Homework Help: Kinetic energy of a flywheel

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