This problem is giving me a headache.(adsbygoogle = window.adsbygoogle || []).push({});

A disk is free to rotate about its center(frictionless) in a vertical axis. A mass m=30grams, pulls down on the disk by means of a light string that is wrapped around the disk. If the radius is 20 cm, Find "I" if the mass falls 1 meter in 2 sec.

We used rT=I(a/r)

so you get .2(.03*9.8)=I(.25/.2)

found velocity using v=s/t

and acceleration using a=v/t

Is this correct? the value for inertia I get is .045 kg m/sec^2

the book has .0222 kg m/s^2

Help

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# Homework Help: Moment of inertia

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