What is the Angular Speed of the Spool After the Bucket Falls?

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SUMMARY

The discussion focuses on calculating the angular speed of a spool after a 3.00 kg bucket falls 4.65 m using conservation of energy principles. Initially, the user incorrectly included the spool's mass in the kinetic energy calculations. After correcting the mass to only account for the bucket, the final calculations yielded an angular speed of 14.06 rad/s. The correct formula applied was based on the conservation of energy, ensuring that only the bucket's mass was used for kinetic energy terms.

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Use conservation of energy to determine the angular speed of the spool shown in Figure P8.36 after the 3.00 kg bucket has fallen 4.65 m, starting from rest. The light string attached to the bucket is wrapped around the spool and does not slip as it unwinds.

I used conservation of energy.
(KEr + KEt + mgh)i = (KEr + KEt + mgh)f
0 + 0 + (3 x 9.8 x 4.65) = [.5(.5Mr^2)w^2] + .5(Mv^2) + 0
136.71 = (.25Mr^2)w^2 + .5Mv^2
136.71 = (.25 x 5 x v^2) + (.5 x 5 x v^2)
v = 7.39
w = 12.324

The ans is not correct, what am i doing wrong?

Thank you for lookin but I manage to see my mistake. I used the wrong mass for the KEt
 

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and KEr. The mass for the KEt and KEr should be the mass of the bucket only not the spool and the bucket. 0 + 0 + (3 x 9.8 x 4.65) = [.5(.5Mb^2)w^2] + .5(Mbv^2) + 0136.71 = (.25Mb^2)w^2 + .5Mbv^2136.71 = (.25 x 3 x v^2) + (.5 x 3 x v^2)v = 6.753w = 14.06
 

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