Calculating Rotational Inertia: A Puzzling Problem?

AI Thread Summary
To calculate the rotational inertia of a wheel with a kinetic energy of 20,300 J at 794 rev/min, the correct formula is K = 1/2 * I * ω². The conversion of 794 rev/min to radians per second is necessary, which results in ω = 83.1 rad/s. After substituting the values into the equation, the rotational inertia I can be found by rearranging the formula to I = 2K/ω². The confusion arises from using the wrong unit for angular velocity, emphasizing the importance of unit conversion in physics calculations. Properly converting to radians per second is crucial for accurate results in rotational dynamics.
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Calculate the rotational inertia of a wheel that has a kinetic energy of 20300 J when rotating at 794 rev/min.
I don't understand this whole rotational inertia thing too well but I thought I found the right equation, but apparently I didn't. I used K = 1/2 * I * w^2
I converted the 794 rev/min to 13.233 rev/s and plugged the numbers into the equation to get 232. The answer is suppose to be in kg*m*m, but withw being in rev/s I don't know what to do.
 
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Convert the w to radians per second
 

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