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Julie323
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Homework Statement
Exactly one turn of a flexible rope with mass m is wrapped around a uniform cylinder with mass M and radius R. The cylinder rotates without friction about a horizontal axle along the cylinder axis. One end of the rope is attached to the cylinder. The cylinder starts with angular speed wo. After one revolution of the cylinder the rope has unwrapped and, at this instant, hangs vertically down, tangent to the cylinder.
a.Find the angular speed of the cylinder at this time. You can ignore the thickness of the rope. (Hint: Use Equation U=mgycm.)
Express your answer in terms of the variables m, M, R, and appropriate constants.
b.Find the linear speed of the lower end of the rope at this time.
Express your answer in terms of the variables m, M, R, and appropriate constants.
Homework Equations
I=.5MR^2
E=Iw^2
The Attempt at a Solution
I initially set it up using the conservation of energy. mgh + .5Iwo^2=.5mv^2 + .5Iwf^2. The thing is, the answer is not dependent upon h (I even tried substituting y for h) and I don't think it it supposed to include v either. Is this equation even correct? Thanks so much for any help!