Rotation, torque, angular momentum?

AI Thread Summary
The discussion revolves around a physics problem involving a uniform solid cylinder unwinding from a tape as it descends. Participants emphasize the importance of identifying forces acting on the cylinder after its release, which is crucial for solving the problem. The need for a clear understanding of concepts like angular momentum and acceleration is highlighted, with suggestions to review class materials for foundational knowledge. Users encourage making an initial attempt at the problem before seeking further assistance. Overall, the thread stresses the significance of grasping basic physics principles to tackle such problems effectively.
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Homework Statement



A cloth tape is wound around the outside of a uniform solid cylinder (mass M, radius R) and fastened to the ceiling as shown in the diagram below. They cylinder is held with the tape vertical and then released from rest. as the cylinder descends, it unwinds from the tape without slipping. The moment of inertia of a uniform solid cylinder about its center is 1/2MR^2.

diagram: http://imgur.com/h0v07

A. draw and label a diagram of the cylinder showing all the forces acting on the cylinder after it is released. label each force clearly.

B. in terms of g, find the downward acceleration of the center of the cylinder as it unrolls from the tape

C. what is the angular velocity of the cylinder after it has descended 3 meters?

D. while descending, does the center of the cylinder move toward the left, toward the right, or straight down? Explain.

Homework Equations



KEr=1/2MR^2

The Attempt at a Solution



i have no clue how to solve this
 
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You need to show us you made some effort before you can get help here. Did you at least do part A?
 
i honestly have no idea where to start...
 
Then I would suggest you go back and read your text, particularly the examples. Identifying the forces is pretty basic. You should have covered it in class weeks ago. You can open a new thread after you've made some sort of attempt at solving the problem on your own.
 
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